Bump crates-index to 0.19.0 since 0.18.12 is yanked due to semver break. (#322)

Author: obi1kenobi

Cargo.lock

@@ -31,7 +31,7 @@ ignore = "0.4.18"
 clap-verbosity-flag = "2.0.0"
 log = "0.4.17"
 git2 = { version = "0.16.0", default-features = false }
-crates-index = { version = "0.18.9", features = ["vendored-openssl"] }
+crates-index = { version = "0.19.0", features = ["vendored-openssl"] }
 human-panic = "1.0.3"
 bugreport = "0.5.0"
 itertools = "0.10.5"