Fix typo in comment

Author: martinburchell

cardinal_pythonlib/openxml/grep_in_openxml.py

@@ -374,7 +374,7 @@ def _search_inner_file(zf: ZipFile, innerfilename: str) -> bool:
                 inner filename
 
         Returns:
-            Ae we done for this ZIP file (should the outer function return)?
+            Are we done for this ZIP file (should the outer function return)?
         """
         nonlocal found_in_zip
         if search_mode == GrepSearchSubstrate.INNER_FILENAME: