Migrate branches gitlab4

[TigreModerata]

Removed branches.py Migrated branch_protector and files_processor where it used branches methods directly. Acceptance tests already exist.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 14.89362% with 40 lines in your changes missing coverage. Please review.

Project coverage is 40.59%. Comparing base (0c85c05) to head (b34a457). Report is 318 commits behind head on main.

Files with missing lines	Patch %	Lines
gitlabform/processors/util/branch_protector.py	13.51%	32 Missing :warning:
gitlabform/processors/project/files_processor.py	20.00%	8 Missing :warning:

:exclamation: There is a different number of reports uploaded between BASE (0c85c05) and HEAD (b34a457). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (0c85c05)	HEAD (b34a457)
	6	5

Additional details and impacted files

@@             Coverage Diff             @@
##             main     #638       +/-   ##
===========================================
- Coverage   67.01%   40.59%   -26.43%     
===========================================
  Files          70       69        -1     
  Lines        2744     2739        -5     
===========================================
- Hits         1839     1112      -727     
- Misses        905     1627      +722     

Files with missing lines	Coverage Δ
gitlabform/gitlab/__init__.py	86.53% <ø> (-11.58%)	:arrow_down:
gitlabform/processors/project/files_processor.py	22.22% <20.00%> (-3.68%)	:arrow_down:
gitlabform/processors/util/branch_protector.py	21.83% <13.51%> (-49.11%)	:arrow_down:

... and 43 files with indirect coverage changes

---- 🚨 Try these New Features:

• Flaky Tests Detection - Detect and resolve failed and flaky tests

[amimas]

Duplicated and completed by #876. Thanks for looking into it.