Improves the performance of the `/repo/search?uid=N` API call, which is used on the user's dashboard to load a repo list. More detailed notes are in https://codeberg.org/forgejo/forgejo/issues/11702.
Removes a redundant query condition (that a user was part of a team in an organization which could see a repo), and a condition that seems incorrect (that a repo could be seen just by being public within a private org, which is incorrect because that doesn't mean the user is a collaborator on the repo).
Covered by over 30 test cases in `repo_list_test.go` which did not fail from these changes. Mutation testing (removing the remaining "2." condition) verified that the codepath is covered as tests did fail.
## Checklist
The [contributor guide](https://forgejo.org/docs/next/contributor/) contains information that will be helpful to first time contributors. There also are a few [conditions for merging Pull Requests in Forgejo repositories](https://codeberg.org/forgejo/governance/src/branch/main/PullRequestsAgreement.md). You are also welcome to join the [Forgejo development chatroom](https://matrix.to/#/#forgejo-development:matrix.org).
### Tests for Go changes
- I added test coverage for Go changes...
- [ ] in their respective `*_test.go` for unit tests.
- [ ] in the `tests/integration` directory if it involves interactions with a live Forgejo server.
- I ran...
- [x] `make pr-go` before pushing
### Documentation
- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [x] I did not document these changes and I do not expect someone else to do it.
### Release notes
- [ ] This change will be noticed by a Forgejo user or admin (feature, bug fix, performance, etc.). I suggest to include a release note for this change.
- [x] This change is not visible to a Forgejo user or admin (refactor, dependency upgrade, etc.). I think there is no need to add a release note for this change.
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/11729
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Mathieu Fenniak <mathieu@fenniak.net>
Co-committed-by: Mathieu Fenniak <mathieu@fenniak.net>