Add gitlab version for deploying sphinx doc

[mmesiti]

from https://github.com/mmesiti/cr-best-practices-in-rse/blob/98b7940782ff1c3cdfb55a433e9d60f735b8f94c/content/gh_workflow.md

Addresses #342

Should go in the direction of coderefinery/git-intro#535

Update: Discovered that the #2 exercise is actually not compatible with the GitLab track. @bast 's suggestion fixes this, rebased this branch on top of #351 . Merging this would also merge #351, so changing this to draft until #351 is merged.

[bast]

Pre-view the result: https://mmesiti.github.io/cr-documentation/branch/gitlab-ci-1/gh_workflow/

[bast]

Suggested change

	hosting in GitHub Pages.
	the two solutions presented above.

[bast]

One thing I would suggest to improve is that the workflow recipes install from a requirements.txt or environment.yml instead of listing the dependencies explicitly. But I know that your PR here did not introduce this so perhaps it should not need to fix it.

Motivation for rather using requirements.txt/environment.yml:

• It connects better to the reproducibility lesson.
• For local preview, a programmer will have to install these anyway and then hopefully from files like requirements.txt/environment.yml.
• And if they need such files anyway, there is less risk to accidentally break the Pages version if both use a consistent dependency list.

But this can become its own issue and does not have to delay this PR.

[mmesiti]

One thing I would suggest to improve is that the workflow recipes install from a requirements.txt or environment.yml instead of listing the dependencies explicitly. But I know that your PR here did not introduce this so perhaps it should not need to fix it.

Motivation for rather using requirements.txt/environment.yml:

* It connects better to the reproducibility lesson.

* For local preview, a programmer will have to install these anyway and then hopefully from files like requirements.txt/environment.yml.

* And if they need such files anyway, there is less risk to accidentally break the Pages version if both use a consistent dependency list.

But this can become its own issue and does not have to delay this PR.

I think it would be better but

• this would require changing also the template repo and add the requirements.txt there, so it's a multi-repo change
• this would be good to do also for the github version that deserves its own issue/

Edit: added #351 and issues/PRs therein

[mmesiti]

Changed to draft because Discovered that the GH-2 exercise is actually not compatible with the GitLab track.

Interestingly, if we merged #351 first, we would not have this problem, since the environment setup would be delegated requirements.txt, so we don't have to change anything workflow/pipeline definition files.

Rebasing this onto #351

[mmesiti]

One thing I would suggest to improve is that the workflow recipes install from a requirements.txt or environment.yml instead of listing the dependencies explicitly.

Turns out this was a smell with interesting consequences :-)