Fix missing license header

Signed-off-by: Łukasz Gryglicki <[email protected]>

Author: lukaszgryglicki

cla-backend/cla/tests/unit/test_ecla.py

@@ -1,3 +1,6 @@
+# Copyright The Linux Foundation and each contributor to CommunityBridge.
+# SPDX-License-Identifier: MIT
+
 import unittest
 from unittest.mock import Mock, patch
 import datetime