Return symlinked path itself if points to the root of a git repo

[yarikoptic]

Ref: #7438 (comment)

• see if there are side effects anywhere in CI
• decide if the right thing to do and add test then
• see how/if would interact with the actual fix for Issue with symlinked top level repository directory #7438

[yarikoptic]

test_bf1886 is effected on various setups -- yet to check...

        # need to use absolute paths
        with chpwd(op.join(parent.path, 'subdir', 'subsubdir')):
            save([op.join(parent.path, 'sub3'),
                  op.join(parent.path, 'subdir', 'subsubdir', 'upup3')])
>       assert_repo_status(parent.path)
..\datalad\core\local\tests\test_save.py:357: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
..\datalad\tests\utils_pytest.py:1664: in assert_repo_status
    eq_(state_files, oktobefound,
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
first = [WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/sub3'), WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/subdir/subsubdir/upup3')]
second = []
msg = 'unexpected content of state "untracked": [WindowsPath(\'C:/DLTMP/datalad_temp_xtr1ag07/sub3\'), WindowsPath(\'C:/DLTMP/datalad_temp_xtr1ag07/subdir/subsubdir/upup3\')] != []'
    def assert_equal(first, second, msg=None):
        if msg is None:
            assert first == second
        else:
>           assert first == second, msg
E           AssertionError: unexpected content of state "untracked": [WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/sub3'), WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/subdir/subsubdir/upup3')] != []
E           assert [WindowsPath(...ubdir/upup3')] == []
E             
E             Left contains 2 more items, first extra item: WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/sub3')
E             
E             Full diff:
E             - []
E             + [
E             +     WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/sub3'),
E             +     WindowsPath('C:/DLTMP/datalad_temp_xtr1ag07/subdir/subsubdir/upup3'),
E             + ]
..\datalad\tests\utils_pytest.py:82: AssertionError
---------- coverage: platform win32, python 3.9.13-final-0 -----------