Enhances authorized integrations (#12261) with a cache of the remote OpenID Connect descriptor file and JSON Web Key Set (JWKS), improving runtime performance and reducing intermittent reliability risks. By default a 10 minute cache is used, configurable through `[authorized_integration].CACHE_TTL`.
To mock the cache for testing, mockery code generation is added, and a previous manually generated mock for `AuthorizationReducer` was replaced with the code generation.
## Checklist
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### Tests for Go changes
- I added test coverage for Go changes...
- [x] 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.
- [ ] 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.
- Authorized integrations are not yet exposed to end-users.
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/12275
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
