Remove schema-utils 3.0 from package.json (incompatibilities resolved)

debian/patches/0740-use-packaged-modules.patch

@@ -3,8 +3,8 @@ Use debian packaged node modules when available
  - Remove webpack-bundle-analyzer
  - Resolve .json files
  - Add more plugins to babel.config.js
- - Add schema-utils 3.0, mkdirp 1.0 and loader-utils 2.0 to ensure compatibility
-   for packaged modules (See #976310)
+ - Add mkdirp 1.0 and loader-utils 2.0 to ensure compatibility for packaged
+   modules (See #976310)
 
 --- a/config/webpack.config.js
 +++ b/config/webpack.config.js
@@ -121,7 +121,7 @@ Use debian packaged node modules when available
      "diff": "^3.4.0",
      "document-register-element": "1.14.3",
      "dompurify": "^2.0.11",
-@@ -85,81 +62,54 @@
+@@ -85,81 +62,53 @@
      "editorconfig": "^0.15.3",
      "emoji-regex": "^7.0.3",
      "emoji-unicode-version": "^0.2.1",
@@ -168,7 +168,6 @@ Use debian packaged node modules when available
 -    "prosemirror-model": "^1.6.4",
      "raphael": "^2.2.7",
 -    "raw-loader": "^4.0.0",
-+    "schema-utils": "^3.0.0",
      "select2": "3.5.2-browserify",
      "smooshpack": "^0.0.62",
      "sortablejs": "^1.10.2",