Don't install gem documentation (!3777) · Merge requests · GitLab.org / GitLab Docs · GitLab

Achilleas Pipinellis - OOO until November 25th (parental leave) requested to merge axil-no-doc into main Apr 18, 2023

What does this MR do and why?

This speeds up the gem installation by skipping the documentation files which we don't need.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

Configure a local GitLab Docs environment: https://gitlab.com/gitlab-org/gitlab-docs/-/blob/main/doc/setup.md.
Check that setup still works:
```
make setup
```