feat(common): add get_repo_dir function and corresponding tests

tests/test_common.py

@@ -2,7 +2,14 @@
 
 from __future__ import annotations
 
-from python.common import bash_wrapper, utcnow
+from python.common import bash_wrapper, get_repo_dir, utcnow
+
+
+def test_get_repo_dir() -> None:
+    """test_get_repo_dir."""
+    repo_dir = get_repo_dir()
+    assert (repo_dir / "pyproject.toml").is_file()
+    assert (repo_dir / "python" / "common.py").is_file()
 
 
 def test_utcnow() -> None: