Merge pull request #17 from adaam2/dependabot/npm_and_yarn/frontend/clean-css-4.1.11

Bump clean-css from 4.1.9 to 4.1.11 in /frontend

Author: adaam2

frontend/yarn.lock

@@ -1566,8 +1566,8 @@ class-utils@^0.3.5:
  static-extend "^0.1.1"
 
 clean-css@4.1.x:
- version "4.1.9"
- resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-4.1.9.tgz#35cee8ae7687a49b98034f70de00c4edd3826301"
+ version "4.1.11"
+ resolved "https://registry.yarnpkg.com/clean-css/-/clean-css-4.1.11.tgz#2ecdf145aba38f54740f26cefd0ff3e03e125d6a"
  dependencies:
  source-map "0.5.x"