chore: remove @babel/plugin-proposal-class-properties

It is included in `@babel/preset-env`

Author: SimenB

babel.config.js

@@ -38,7 +38,6 @@ module.exports = {
   ],
   plugins: [
     ['@babel/plugin-transform-modules-commonjs', {allowTopLevelThis: true}],
-    '@babel/plugin-proposal-class-properties',
     require.resolve('./scripts/babel-plugin-jest-require-outside-vm'),
   ],
   presets: [

package.json

@@ -4,7 +4,6 @@
   "version": "0.0.0",
   "devDependencies": {
     "@babel/core": "^7.3.4",
-    "@babel/plugin-proposal-class-properties": "^7.3.4",
     "@babel/plugin-transform-modules-commonjs": "^7.1.0",
     "@babel/preset-env": "^7.1.0",
     "@babel/preset-react": "^7.0.0",