MDL-77559 js: Revert "MDL-75012 js: Bump Babel dependencies"

This reverts commit c90054e98e.

.grunt/tasks/javascript.js

@@ -127,7 +127,7 @@ module.exports = grunt => {
         };
     };
 
-    const terser = require('@rollup/plugin-terser');
+    const terser = require('rollup-plugin-terser').terser;
     grunt.config.merge({
         rollup: {
             options: {
@@ -136,13 +136,6 @@ module.exports = grunt => {
                 sourcemap: true,
                 treeshake: false,
                 context: 'window',
-
-                // Treat all modules as external and do not try to resolve them.
-                // https://rollupjs.org/configuration-options/#external
-                // We do not need to resolve them as each module is transpiled individually and there is no tree shaking
-                // or combining of dependencies.
-                external: true,
-
                 plugins: [
                     rateLimit(),
                     babel({

package.json

@@ -4,15 +4,14 @@
   "description": "Moodle",
   "devDependencies": {
     "@babel/core": "7.17.5",
-    "@babel/eslint-parser": "^7.19.1",
     "@babel/plugin-proposal-class-properties": "7.16.7",
     "@babel/plugin-proposal-json-strings": "7.16.7",
     "@babel/plugin-syntax-dynamic-import": "7.8.3",
     "@babel/plugin-syntax-import-meta": "7.10.4",
     "@babel/preset-env": "7.16.11",
-    "@rollup/plugin-terser": "^0.4.0",
     "ajv": "^8.12.0",
     "async": "^3.2.4",
+    "babel-eslint": "10.1.0",
     "babel-plugin-system-import-transformer": "^4.0.0",
     "babel-plugin-transform-es2015-modules-amd-lazy": "2.0.1",
     "cross-env": "^7.0.3",
@@ -39,7 +38,7 @@
     "node-sass": "^8.0.0",
     "npm-run-all": "^4.1.5",
     "postcss-scss": "^4.0.6",
-    "rollup": "^3.17.3",
+    "rollup-plugin-terser": "^7.0.2",
     "semver": "^7.3.8",
     "shifter": "https://github.com/andrewnicols/shifter/releases/download/v1.2.0_moodle-slim-0/shifter-1.2.0_moodle-slim-0.tar.gz",
     "stylelint": "^14.16.1",
@@ -50,6 +49,9 @@
   "engines": {
     "node": ">=18.12.0 <19"
   },
+  "dependencies": {
+    "@babel/eslint-parser": "^7.17.0"
+  },
   "browserslist": [
     ">0.3%",
     "last 2 versions",