* Improve webhooks

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Update MSTeams and ReviewPayload comment

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* Add repo.FullName to comments

Signed-off-by: jolheiser <john.olheiser@gmail.com>

* fix bug on pull requests when transfer head repository

* add migration and fix lint

* fix tests and add a cache check on LoadBaseRepo

Signed-off-by: jolheiser <john.olheiser@gmail.com>

This PR fixes #7598 by providing a configurable way of signing commits across the Gitea instance. Per repository configurability and import/generation of trusted secure keys is not provided by this PR - from a security PoV that's probably impossible to do properly. Similarly web-signing, that is asking the user to sign something, is not implemented - this could be done at a later stage however.

## Features
- [x] If commit.gpgsign is set in .gitconfig sign commits and files created through repofiles. (merges should already have been signed.)
- [x] Verify commits signed with the default gpg as valid
- [x] Signer, Committer and Author can all be different
    - [x] Allow signer to be arbitrarily different - We still require the key to have an activated email on Gitea. A more complete implementation would be to use a keyserver and mark external-or-unactivated with an "unknown" trust level icon.
- [x] Add a signing-key.gpg endpoint to get the default gpg pub key if available
    - Rather than add a fake web-flow user I've added this as an endpoint on /api/v1/signing-key.gpg
    - [x] Try to match the default key with a user on gitea - this is done at verification time
- [x] Make things configurable?
    - app.ini configuration done
    - [x] when checking commits are signed need to check if they're actually verifiable too
- [x] Add documentation

I have decided that adjusting the docker to create a default gpg key is not the correct thing to do and therefore have not implemented this.

* move AddTestPullRequestTask to pull service package from models

* fix fmt

* Change tests to make it possible to run TestGit with 1.7.2

* Make merge run on 1.7.2

* Fix tracking and staging branch name problem

* Ensure that git 1.7.2 works on tests

* ensure that there is no chance for conflicts

* Fix-up missing merge issues

* Final rm

* Ensure LFS filters run on the tests

* Do not sign commits from temp repo

* Restore tracking fetch change

* Apply suggestions from code review

* Update modules/repofiles/temp_repo.go

Signed-off-by: Elias Norberg <elias@aisle.se>

* extract actions on new pull request from models to pulls service

* improve code

* move code.gitea.io/gitea/modules/pull to code.gitea.io/gitea/services/pull

* fix fmt

* Rename pulls.go to pull.go