Bump @babel/plugin-proposal-class-properties from 7.5.0 to 7.5.5 (#11661)

Bumps [@babel/plugin-proposal-class-properties](https://github.com/babel/babel) from 7.5.0 to 7.5.5.
- [Release notes](https://github.com/babel/babel/releases)
- [Changelog](https://github.com/babel/babel/blob/master/CHANGELOG.md)
- [Commits](https://github.com/babel/babel/compare/v7.5.0...v7.5.5)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -60,7 +60,7 @@
   "private": true,
   "dependencies": {
     "@babel/core": "^7.4.5",
-    "@babel/plugin-proposal-class-properties": "^7.5.0",
+    "@babel/plugin-proposal-class-properties": "^7.5.5",
     "@babel/plugin-proposal-decorators": "^7.4.4",
     "@babel/plugin-proposal-object-rest-spread": "^7.4.4",
     "@babel/plugin-syntax-dynamic-import": "^7.2.0",