chore(css): Move CSS files to src directory

[juliusknorr]

Move all files in css/ to the src/ directory since they are only used in the webpack build.

This has two positive effects:

• PRs like fix: clickable zone of task list checkbox #4312 will properly fail on the node test now as it is not skipped
• Running sass build in server should no longer trigger a build of those files in text

🏁 Checklist

• Code is properly formatted (npm run lint / npm run stylelint / composer run cs:check)
• Sign-off message is added to all commits
• Tests (unit, integration and/or end-to-end) passing and the changes are covered with tests
• Documentation (README or documentation) has been updated or is not required

[cypress]

2 failed and 2 flaky tests on run #10314 ↗︎

2

143

1

2

2

Details:

chore(css): Move CSS files to src directory
Project: Text	Commit: b4244b0500
Status: Failed	Duration: 11:22 💡
Started: Jun 20, 2023 9:36 AM	Ended: Jun 20, 2023 9:48 AM

  conflict.spec.js • 1 failed test

View Output Video

Test		Artifacts
text/plain (lines.txt) > displays conflicts		Output Screenshots

  api/UsersApi.spec.js • 1 failed test

View Output Video

Test		Artifacts
The user mention API > fetches users with valid session		Output Screenshots

  sync.spec.js • 1 flaky test

View Output Video

Test		Artifacts
Sync > recovers from a lost connection		Output Screenshots

  nodes/HardBreak.spec.js • 1 flaky test

View Output Video

Test		Artifacts
Hard break support > Convert paragraph break into hard break		Output Screenshots

_{This comment has been generated by cypress-bot as a result of this project's GitHub integration settings.}

[juliusknorr]

/compile

[juliusknorr]

Failures unrelated