Update git_utils.py: warn on long paths issue on Windows

Author: BareninVitalya

src/gitingest/utils/git_utils.py

@@ -87,6 +87,7 @@ async def ensure_git_installed() -> None:
     ------
     RuntimeError
         If Git is not installed or not accessible, or if enabling long paths fails.
+        If checking the long path setting fails on Windows.
 
     """
     try: