1) Added release note for v7.7

2) Added exception handling while removing the test database file.

web/regression/python_test_utils/test_utils.py

@@ -954,7 +954,11 @@ def reset_layout_db(user_id=None):
 def remove_db_file():
     """This function use to remove SQLite DB file"""
     if os.path.isfile(config.TEST_SQLITE_PATH):
-        os.remove(config.TEST_SQLITE_PATH)
+        try:
+            os.remove(config.TEST_SQLITE_PATH)
+        except PermissionError:
+            # TODO: Added for issue 6164
+            pass
 
 
 def _cleanup(tester, app_starter):