test: handle symlinked Git directories in refresh checks

The macOS Python 3.8 and 3.14 CI jobs each passed 1,348 tests but failed
`test_refresh_with_good_relative_git_path_arg`. Installing the supported
Homebrew Git exposes `/opt/homebrew/opt/git/bin` on `PATH`; changing into
that directory resolves it to the versioned Cellar directory.

Compute the expected relative executable path from the current directory
after changing into it. This preserves the documented `Git.refresh()`
behavior and executable symlinks while removing the test's assumption
that `shutil.which()` and `os.getcwd()` retain the same directory spelling.

Validation: reproduced the failure using a symlinked directory on `PATH`.
All 36 refresh tests pass with both ordinary and symlinked `PATH` values.
Ruff lint, Ruff format, and `git diff --check` pass.

Author: codex

test/test_git.py

@@ -814,9 +814,11 @@ def test_refresh_with_good_relative_git_path_arg(self):
         dirname, basename = osp.split(absolute_path)
 
         with cwd(dirname):
+            # getcwd may resolve directory symlinks, such as Homebrew's opt/git in PATH.
+            expected_path = osp.join(os.getcwd(), basename)
             with _rollback_refresh():
                 refresh(basename)
-                self.assertEqual(self.git.GIT_PYTHON_GIT_EXECUTABLE, absolute_path)
+                self.assertEqual(self.git.GIT_PYTHON_GIT_EXECUTABLE, expected_path)
 
     def test_version_info_is_cached(self):
         fake_version_info = (123, 456, 789)