Fix post-migrate hooks

[mdellweg]

Post migrate hooks are called after every migration. So they must be resilient against missing or differently looking models. Either they take the models from the passed apps and suppress LookupError or they should suppress both LookupError and ProgrammingError.

📜 Checklist

• Commits are cleanly separated with meaningful messages (simple features and bug fixes should be squashed to one commit)
• A changelog entry or entries has been added for any significant changes
• Follows the Pulp policy on AI Usage
• (For new features) - User documentation and test coverage has been added

See: Pull Request Walkthrough

[patchback]

Backport to 3.117: 💚 backport PR created

✅ Backport PR branch: patchback/backports/3.117/bed13b0be7be8421e345338795f5506f8693a736/pr-8060

Backported as #8062

🤖 @patchback
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my source is open — https://github.com/sanitizers/patchback-github-app.

[patchback]

Backport to 3.105: 💚 backport PR created

✅ Backport PR branch: patchback/backports/3.105/bed13b0be7be8421e345338795f5506f8693a736/pr-8060

Backported as #8063

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.

[patchback]

Backport to 3.85: 💚 backport PR created

✅ Backport PR branch: patchback/backports/3.85/bed13b0be7be8421e345338795f5506f8693a736/pr-8060

Backported as #8064

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.

[patchback]

Backport to 3.73: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply bed13b0 on top of patchback/backports/3.73/bed13b0be7be8421e345338795f5506f8693a736/pr-8060

Backporting merged PR #8060 into main

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   git remote add upstream https://github.com/pulp/pulpcore.git
   

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   git fetch upstream
   git checkout -b patchback/backports/3.73/bed13b0be7be8421e345338795f5506f8693a736/pr-8060 upstream/3.73
   

4. Now, cherry-pick PR Fix post-migrate hooks #8060 contents into that branch:

   git cherry-pick -x bed13b0be7be8421e345338795f5506f8693a736
   

   If it'll yell at you with something like fatal: Commit bed13b0be7be8421e345338795f5506f8693a736 is a merge but no -m option was given., add -m 1 as follows instead:

   git cherry-pick -m1 -x bed13b0be7be8421e345338795f5506f8693a736
   

5. At this point, you'll encounter some merge conflicts. You must
   resolve them in order to preserve the patch from PR Fix post-migrate hooks #8060 as close to the
   original as possible.
6. Once conflicts are resolved and git added, run:

   git cherry-pick --continue
   

7. Push this branch to your fork on GitHub:

   git push origin patchback/backports/3.73/bed13b0be7be8421e345338795f5506f8693a736/pr-8060
   

8. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.