Bump gulp-clean-css from 2.0.12 to 4.3.0

Bumps [gulp-clean-css](https://github.com/scniro/gulp-clean-css) from 2.0.12 to 4.3.0.
- [Release notes](https://github.com/scniro/gulp-clean-css/releases)
- [Commits](https://github.com/scniro/gulp-clean-css/commits/4.3.0)

---
updated-dependencies:
- dependency-name: gulp-clean-css
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -6,7 +6,7 @@
     "browsernizr": "2.1.0",
     "es6-promise": "4.2.8",
     "gulp": "3.9.1",
-    "gulp-clean-css": "2.0.12",
+    "gulp-clean-css": "4.3.0",
     "gulp-concat-css": "2.3.0",
     "gulp-postcss": "6.1.1",
     "gulp-replace": "0.5.4",

yarn.lock

@@ -409,12 +409,6 @@ buffer@^4.1.0:
     ieee754 "^1.1.4"
     isarray "^1.0.0"
 
-bufferstreams@1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/bufferstreams/-/bufferstreams-1.0.1.tgz#cfb1ad9568d3ba3cfe935ba9abdd952de88aab2a"
-  dependencies:
-    readable-stream "^1.0.33"
-
 builtin-modules@^1.0.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/builtin-modules/-/builtin-modules-1.1.1.tgz#270f076c5a72c02f5b65a47df94c5fe3a278892f"
@@ -484,12 +478,11 @@ cipher-base@^1.0.0, cipher-base@^1.0.1:
   dependencies:
     inherits "^2.0.1"
 
-clean-css@^3.4.19:
-  version "3.4.25"
-  resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-3.4.25.tgz#9e9a52d5c1e6bc5123e1b2783fa65fe958946ede"
+clean-css@4.2.3:
+  version "4.2.3"
+  resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-4.2.3.tgz#507b5de7d97b48ee53d84adb0160ff6216380f78"
   dependencies:
-    commander "2.8.x"
-    source-map "0.4.x"
+    source-map "~0.6.0"
 
 cliui@^2.1.0:
   version "2.1.0"
@@ -556,12 +549,6 @@ combined-stream@^1.0.5, combined-stream@~1.0.5:
   dependencies:
     delayed-stream "~1.0.0"
 
-commander@2.8.x:
-  version "2.8.1"
-  resolved "https://registry.yarnpkg.com/commander/-/commander-2.8.1.tgz#06be367febfda0c330aa1e2a072d3dc9762425d4"
-  dependencies:
-    graceful-readlink ">= 1.0.0"
-
 concat-map@0.0.1:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"
@@ -1161,20 +1148,14 @@ graceful-fs@~1.2.0:
   version "1.2.3"
   resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-1.2.3.tgz#15a4806a57547cb2d2dbf27f42e89a8c3451b364"
 
-"graceful-readlink@>= 1.0.0":
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/graceful-readlink/-/graceful-readlink-1.0.1.tgz#4cafad76bc62f02fa039b2f94e9a3dd3a391a725"
-
-gulp-clean-css@2.0.12:
-  version "2.0.12"
-  resolved "https://registry.yarnpkg.com/gulp-clean-css/-/gulp-clean-css-2.0.12.tgz#c43522154bccc66b4a136dc928d77aa0819a1a67"
+gulp-clean-css@4.3.0:
+  version "4.3.0"
+  resolved "https://registry.yarnpkg.com/gulp-clean-css/-/gulp-clean-css-4.3.0.tgz#5b1e73f2fca46703eb636014cdd4553cea65146d"
   dependencies:
-    clean-css "^3.4.19"
-    gulp-util "^3.0.7"
-    object-assign "^4.1.0"
-    readable-stream "^2.1.4"
-    vinyl-bufferstream "^1.0.1"
-    vinyl-sourcemaps-apply "^0.2.1"
+    clean-css "4.2.3"
+    plugin-error "1.0.1"
+    through2 "3.0.1"
+    vinyl-sourcemaps-apply "0.2.1"
 
 gulp-concat-css@2.3.0:
   version "2.3.0"
@@ -2366,7 +2347,7 @@ pinkie@^2.0.0:
   version "2.0.4"
   resolved "https://registry.yarnpkg.com/pinkie/-/pinkie-2.0.4.tgz#72556b80cfa0d48a974e80e77248e80ed4f7f870"
 
-plugin-error@^1.0.1:
+plugin-error@1.0.1, plugin-error@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/plugin-error/-/plugin-error-1.0.1.tgz#77016bd8919d0ac377fdcdd0322328953ca5781c"
   dependencies:
@@ -2501,7 +2482,7 @@ read-pkg@^1.0.0:
     isarray "0.0.1"
     string_decoder "~0.10.x"
 
-"readable-stream@>=1.1.13-1 <1.2.0-0", readable-stream@^1.0.33, readable-stream@~1.1.9:
+"readable-stream@>=1.1.13-1 <1.2.0-0", readable-stream@~1.1.9:
   version "1.1.14"
   resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-1.1.14.tgz#7cf4c54ef648e3813084c636dd2079e166c081d9"
   dependencies:
@@ -2510,7 +2491,7 @@ read-pkg@^1.0.0:
     isarray "0.0.1"
     string_decoder "~0.10.x"
 
-"readable-stream@^2.0.0 || ^1.1.13", readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.1.0, readable-stream@^2.1.4, readable-stream@^2.1.5:
+"readable-stream@^2.0.0 || ^1.1.13", readable-stream@^2.0.1, readable-stream@^2.0.2, readable-stream@^2.1.0, readable-stream@^2.1.5:
   version "2.2.6"
   resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.2.6.tgz#8b43aed76e71483938d12a8d46c6cf1a00b1f816"
   dependencies:
@@ -2767,12 +2748,6 @@ source-map-url@~0.3.0:
   version "0.3.0"
   resolved "https://registry.yarnpkg.com/source-map-url/-/source-map-url-0.3.0.tgz#7ecaf13b57bcd09da8a40c5d269db33799d4aaf9"
 
-source-map@0.4.x:
-  version "0.4.4"
-  resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.4.4.tgz#eba4f5da9c0dc999de68032d8b4f76173652036b"
-  dependencies:
-    amdefine ">=0.0.4"
-
 source-map@^0.1.38:
   version "0.1.43"
   resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.1.43.tgz#c24bc146ca517c1471f5dacbe2571b2b7f9e3346"
@@ -2783,7 +2758,7 @@ source-map@^0.5.1, source-map@^0.5.6, source-map@~0.5.1, source-map@~0.5.3:
   version "0.5.6"
   resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.5.6.tgz#75ce38f52bf0733c5a7f0c118d81334a2bb5f412"
 
-source-map@^0.6.1:
+source-map@^0.6.1, source-map@~0.6.0:
   version "0.6.1"
   resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.6.1.tgz#74722af32e9614e9c287a8d0bbde48b5e2f1a263"
 
@@ -2941,6 +2916,12 @@ textextensions@~1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/textextensions/-/textextensions-1.0.2.tgz#65486393ee1f2bb039a60cbba05b0b68bd9501d2"
 
+through2@3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/through2/-/through2-3.0.1.tgz#39276e713c3302edf9e388dd9c812dd3b825bd5a"
+  dependencies:
+    readable-stream "2 || 3"
+
 through2@^0.6.1:
   version "0.6.5"
   resolved "https://registry.yarnpkg.com/through2/-/through2-0.6.5.tgz#41ab9c67b29d57209071410e1d7a7a968cd3ad48"
@@ -3129,12 +3110,6 @@ vinyl-buffer@1.0.0:
     bl "^0.9.1"
     through2 "^0.6.1"
 
-vinyl-bufferstream@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/vinyl-bufferstream/-/vinyl-bufferstream-1.0.1.tgz#0537869f580effa4ca45acb47579e4b9fe63081a"
-  dependencies:
-    bufferstreams "1.0.1"
-
 vinyl-fs@^0.3.0:
   version "0.3.14"
   resolved "https://registry.yarnpkg.com/vinyl-fs/-/vinyl-fs-0.3.14.tgz#9a6851ce1cac1c1cea5fe86c0931d620c2cfa9e6"
@@ -3155,7 +3130,7 @@ vinyl-source-stream@1.1.0:
     through2 "^0.6.1"
     vinyl "^0.4.3"
 
-vinyl-sourcemaps-apply@^0.2.0, vinyl-sourcemaps-apply@^0.2.1:
+vinyl-sourcemaps-apply@0.2.1, vinyl-sourcemaps-apply@^0.2.0:
   version "0.2.1"
   resolved "https://registry.yarnpkg.com/vinyl-sourcemaps-apply/-/vinyl-sourcemaps-apply-0.2.1.tgz#ab6549d61d172c2b1b87be5c508d239c8ef87705"
   dependencies: