Restrict imports from any out/ directories (#41515)

* Restrict imports from any `out/` directories

.eslintrc.js

@@ -84,6 +84,11 @@ See https://handbook.sourcegraph.com/community/faq#is-all-of-sourcegraph-open-so
             message:
               'Imports from package internals are banned. Add relevant export to the entry point of the package to import it from the outside world.',
           },
+          {
+            group: ['**/out/*'],
+            message:
+              "Please don't import stuff from the 'out' directory. It’s generated code. Remove the 'out/' part and you should be good go to.",
+          },
         ],
       },
     ],

client/build-config/src/esbuild/monacoPlugin.ts

@@ -1,7 +1,9 @@
 import path from 'path'
 
 import * as esbuild from 'esbuild'
+// eslint-disable-next-line no-restricted-imports
 import { EditorFeature, featuresArr } from 'monaco-editor-webpack-plugin/out/features'
+// eslint-disable-next-line no-restricted-imports
 import { EditorLanguage, languagesArr } from 'monaco-editor-webpack-plugin/out/languages'
 
 import { MONACO_LANGUAGES_AND_FEATURES } from '@sourcegraph/build-config'