[IMP] upgrade-util: link code documentation

[aj-fuentes]

Add direct code documentation from upgrade-util repo.

[robodoo]

Pull request status dashboard.

[Feyensv]

Checklist before merge:

PR:

• Do not fail in an ugly way if odoo sources is there but upgrade util is not
• make github links work

Runbot:

• Upgrade util bundles must trigger a documentation build (to make sure the doc is still building correctly with the changes in upgrade-util)
• Documentation builds need to fetch upgrade util repo (runbot won't be green before anyway, and you're already talking about it with XDO)
• How to make sure the build of documentation is green on all versions even if upgrade-util is not versioned ? What if we rename one util (we potentially have x doc PRs to merge at the same time, with one upgrade-util PR)
  -> [XDO] feasible: but we won't do it for now
• Assign upgrade team as codeowner for the upgrades folder ? (ci/codeowner-coverage must be green)
  -> [ANV] Assign doc-review* instead and we'll request a review if needed.
  -> [VFE] doc-review

Internal:

• nightly documentation build script must fetch upgrade-util too (or the script will fail and the doc won't be updated anymore)

[aj-fuentes]

The last patch to conf.py works for Custom documentation build

[Feyensv]

Added 3 commits (that can be squashed into main ones) to highlight/propose some improvements.

If we could reduce the correlation between doc and upgrade by keeping references less specific, you would be able to make changes in your repository more easily (and the documentation might be added automatically, without having to make any change on the documentation repository).

[aj-fuentes]

@Feyensv thanks for the fixups :)

I pushed one more that makes everything automatic. That was the actual goal and I think with your setup it can be achieved nicely. I added the private tag to the functions that we do not want to expose or that still need better docs -- I may add some of them soon.

See the latest build and sibling PR for the last docs. I think it's mostly all there.

[AntoineVDV]

The PR should target 15.0 before merging.

[Feyensv]

@AntoineVDV 16.0, upgrade doc was merged in 16.0 with #7330

[AntoineVDV]

16.0 then, but not master

[aj-fuentes]

@AntoineVDV, as discussed with @Feyensv in DM, I've squashed the changes into two commits one for the infra changes another for the proper docs changes. I created the PR targeting 16.0 #8748 -- to be updated once all here is settled as per TODO list

[Feyensv]

Runbot matters have been handled

• Upgrade-util builds will now trigger a documentation build
• Doc builds will now fetch upgrade-util sources

After confirmation that the nightly script of the doc has been updated to fetch the upgrade-util sources, we will have to merge the upgrade-util PR (odoo/upgrade-util#66) (with or without this PR) before merging the 16.0 one (since it'll won't be green unless the util docstrings have been updated).

[aj-fuentes]

I'm closing this PR to allow odoo/upgrade-util#66 to be merged.