Add CORTEX_VERSION comment to client.py

Author: deliahu

pkg/workloads/cortex/client/cortex/client.py

@@ -44,7 +44,7 @@ def __init__(self, aws_access_key_id, aws_secret_access_key, operator_url):
         self.aws_access_key_id = aws_access_key_id
         self.aws_secret_access_key = aws_secret_access_key
         self.headers = {
-            "CortexAPIVersion": "master",
+            "CortexAPIVersion": "master",  # CORTEX_VERSION
             "Authorization": "CortexAWS {}|{}".format(
                 self.aws_access_key_id, self.aws_secret_access_key
             ),