Re-add babel plugins for dynamic imports

With https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/25597 we
also removed the babel-plugin-dynamic-import-node. It is now throwing
errors when we run jest with coverage.

babel.config.js

@@ -41,6 +41,11 @@ if (BABEL_ENV === 'karma' || BABEL_ENV === 'coverage') {
 // Jest is running in node environment
 if (BABEL_ENV === 'jest') {
   plugins.push('@babel/plugin-transform-modules-commonjs');
+  /*
+  without the following, babel-plugin-istanbul throws an error:
+  https://gitlab.com/gitlab-org/gitlab-ce/issues/58390
+  */
+  plugins.push('babel-plugin-dynamic-import-node');
 }
 
 module.exports = { presets, plugins };

package.json

@@ -134,6 +134,7 @@
     "@vue/test-utils": "^1.0.0-beta.25",
     "axios-mock-adapter": "^1.15.0",
     "babel-jest": "^24.1.0",
+    "babel-plugin-dynamic-import-node": "^2.2.0",
     "babel-plugin-istanbul": "^5.1.0",
     "babel-plugin-rewire": "^1.2.0",
     "chalk": "^2.4.1",

yarn.lock

@@ -1466,6 +1466,13 @@ babel-loader@^8.0.5:
     mkdirp "^0.5.1"
     util.promisify "^1.0.0"
 
+babel-plugin-dynamic-import-node@^2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/babel-plugin-dynamic-import-node/-/babel-plugin-dynamic-import-node-2.2.0.tgz#c0adfb07d95f4a4495e9aaac6ec386c4d7c2524e"
+  integrity sha512-fP899ELUnTaBcIzmrW7nniyqqdYWrWuJUyPWHxFa/c7r7hS6KC8FscNfLlBNIoPSc55kYMGEEKjPjJGCLbE1qA==
+  dependencies:
+    object.assign "^4.1.0"
+
 babel-plugin-istanbul@^5.1.0:
   version "5.1.0"
   resolved "https://registry.yarnpkg.com/babel-plugin-istanbul/-/babel-plugin-istanbul-5.1.0.tgz#6892f529eff65a3e2d33d87dc5888ffa2ecd4a30"