Fix sync list_shares test leaking shares due to wrong cleanup prefix (#47595)

Author: weirongw23-msft

sdk/storage/azure-storage-file-share/tests/test_share.py

@@ -953,7 +953,7 @@ def test_list_shares_with_num_results_and_marker(self, **kwargs):
         assert len(shares2) == 2
         self.assertNamedItemInContainer(shares2, share_names[2])
         self.assertNamedItemInContainer(shares2, share_names[3])
-        self._delete_shares()
+        self._delete_shares(prefix)
 
     @FileSharePreparer()
     @recorded_by_proxy