* [FEATURE] [API] Add Endpoint for Branch Creation

Issue: https://github.com/go-gitea/gitea/issues/11376

This commit introduces an API endpoint for branch creation.

The added route is POST /repos/{owner}/{repo}/branches.
A JSON with the name of the new branch and the name of the old branch is
required as parameters.

Signed-off-by: Terence Le Huu Phuong <terence@qwasar.io>

* Put all the logic into CreateBranch and removed CreateRepoBranch

* - Added the error ErrBranchDoesNotExist in error.go
- Made the CreateNewBranch function return an errBranchDoesNotExist error
when the OldBranch does not exist
- Made the CreateBranch API function checks that the repository is not
empty and that branch exists.

* - Added a resetFixtures helper function in integration_test.go to
fine-tune test env resetting
- Added api test for CreateBranch
- Used resetFixture instead of the more general prepareTestEnv in the
repo_branch_test CreateBranch tests

* Moved the resetFixtures call inside the loop for APICreateBranch function

* Put the prepareTestEnv back in repo_branch_test

* fix import order/sort api branch test

Co-authored-by: zeripath <art27@cantab.net>

* switch to use pseudorandom generator and stop cloning in pushcreate

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Add some logging of BranchProtectPRMerge

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Stop running prepareTestEnv so often for TestAPIGetBranch

Signed-off-by: Andrew Thornton <art27@cantab.net>

* use same process as in routers/repo/branch.go/deleteBranch

* make sure default branch can not be deleted

* remove IsDefaultBranch from UI process - it is worth its own pull

* permissions

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

* add API branch protection endpoint

* lint

* Change to use team names instead of ids.

* Status codes.

* fix

* Fix

* Add new branch protection options (BlockOnRejectedReviews, DismissStaleApprovals, RequireSignedCommits)

* Do xorm query directly

* fix xorm GetUserNamesByIDs

* Add some tests

* Improved GetTeamNamesByID

* http status created for CreateBranchProtection

* Correct status code in integration test

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: zeripath <art27@cantab.net>

* Fix data race in testlogger

* Update git_helper_for_declarative_test.go

* move sdk structs to moduels/structs

* fix tests

* fix fmt

* fix swagger

* fix vendor

* Helper functions for intergration test boilerplate