Remove only usage of Webpack aliases and resolver, incompatible with new setup

.eslintrc

@@ -8,7 +8,7 @@
   "settings": {
     "import/resolver": {
       "webpack": {
-        "config": "webpack/prod.config.js"
+        "config": "client/webpack.config.js"
       }
     }
   },

client/webpack.config.js

@@ -42,9 +42,6 @@ module.exports = function exports() {
     ],
     resolve: {
       extensions: ['.ts', '.tsx', '.js'],
-      alias: {
-        'wagtail-client': path.resolve('.', 'client'),
-      },
     },
     module: {
       rules: [

wagtail/admin/static_src/wagtailadmin/app/wagtailadmin.entry.js

@@ -9,7 +9,7 @@ import {
   initSkipLink,
   initIE11Warning,
   initUpgradeNotification,
-} from 'wagtail-client';
+} from '../../../../../client/src/index';
 
 if (process.env.NODE_ENV === 'development') {
   // Run react-axe in development only, so it does not affect performance