chore(deps): update dependency @ember/string to v4 (#472)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

docs-app/package.json

@@ -36,7 +36,7 @@
     "@docfy/core": "^0.8.0",
     "@docfy/ember": "^0.8.0",
     "@ember/optional-features": "^2.0.0",
-    "@ember/string": "^3.0.1",
+    "@ember/string": "^4.0.0",
     "@ember/test-helpers": "^3.1.0",
     "@embroider/compat": "^2.0.0",
     "@embroider/core": "2.1.1",

pnpm-lock.yaml

@@ -34,7 +34,7 @@
     "@crowdstrike/ember-toucan-form": "workspace:*",
     "@crowdstrike/ember-toucan-styles": "^3.0.0",
     "@ember/optional-features": "^2.0.0",
-    "@ember/string": "^3.0.1",
+    "@ember/string": "^4.0.0",
     "@ember/test-helpers": "^3.1.0",
     "@embroider/test-setup": "^2.0.0",
     "@glimmer/component": "^1.1.2",