Remove unused branches from mock module

[cjw296]

Also exclude a couple of methods from coverage checking in the downstream rolling backport of mock

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot ARM Raspbian 3.x has failed when building commit e6379f7.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/all/#builders/424/builds/4405) and take a look at the build logs.
4. Check if the failure is related to this commit (e6379f7) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/all/#builders/424/builds/4405

Summary of the results of the build (if available):

== Tests result: ENV CHANGED ==

426 tests OK.

10 slowest tests:

• test_venv: 9 min 44 sec
• test_largefile: 9 min 30 sec
• test_compileall: 7 min 17 sec
• test_pathlib: 4 min 48 sec
• test_math: 4 min 19 sec
• test_multiprocessing_spawn: 4 min 8 sec
• test_concurrent_futures: 3 min 14 sec
• test_peg_generator: 2 min 18 sec
• test_support: 2 min 16 sec
• test_hashlib: 2 min 15 sec

1 test altered the execution environment:
test.test_asyncio.test_unix_events

19 tests skipped:
test.test_asyncio.test_windows_events
test.test_asyncio.test_windows_utils test_devpoll test_idle
test_ioctl test_kqueue test_launcher test_perf_profiler
test_startfile test_tcl test_tkinter test_ttk test_ttk_textonly
test_turtle test_winconsoleio test_winreg test_winsound test_wmi
test_zipfile64

Total duration: 37 min 37 sec

Click to see traceback logs

remote: Enumerating objects: 9, done.        
remote: Counting objects:  11% (1/9)        
remote: Counting objects:  22% (2/9)        
remote: Counting objects:  33% (3/9)        
remote: Counting objects:  44% (4/9)        
remote: Counting objects:  55% (5/9)        
remote: Counting objects:  66% (6/9)        
remote: Counting objects:  77% (7/9)        
remote: Counting objects:  88% (8/9)        
remote: Counting objects: 100% (9/9)        
remote: Counting objects: 100% (9/9), done.        
remote: Compressing objects:  16% (1/6)        
remote: Compressing objects:  33% (2/6)        
remote: Compressing objects:  50% (3/6)        
remote: Compressing objects:  66% (4/6)        
remote: Compressing objects:  83% (5/6)        
remote: Compressing objects: 100% (6/6)        
remote: Compressing objects: 100% (6/6), done.        
remote: Total 9 (delta 3), reused 5 (delta 3), pack-reused 0        
From https://github.com/python/cpython
 * branch                  main       -> FETCH_HEAD
Note: switching to 'e6379f72cbc60f6b3c5676f9e225d4f145d5693f'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by switching back to a branch.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -c with the switch command. Example:

  git switch -c <new-branch-name>

Or undo this operation with:

  git switch -

Turn off this advice by setting config variable advice.detachedHead to false

HEAD is now at e6379f72cb Remove unused branches from mock module (#106617)
Switched to and reset branch 'main'

./Modules/_testcapi/heaptype_relative.c: In function ‘make_sized_heaptypes’:
./Modules/_testcapi/heaptype_relative.c:62:28: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
   62 |                            (unsigned long long)data_ptr,
      |                            ^

make: *** [Makefile:2017: buildbottest] Error 3