Add yarn clean step, to delete production compiled assets (!19212) · Merge requests · GitLab.org / GitLab FOSS · GitLab

What does this MR do?

Adds a yarn script to delete production compiled assets

Does this MR meet the acceptance criteria?

Changelog entry added, if necessary
Documentation created/updated
Conform by the code review guidelines
- Has been reviewed by a Frontend maintainer
Conform by the merge request performance guides
Conform by the style guides