Add new header

Author: rayokota

src/confluent_kafka/schema_registry/_async/schema_registry_client.py

@@ -441,7 +441,7 @@ async def send_request(
             body = json.dumps(body)
             headers = {'Content-Length': str(len(body)),
                        'Content-Type': "application/vnd.schemaregistry.v1+json",
-                       'Accept-Version': "8.0"}
+                       'Confluent-Accept-Unknown-Properties': "true"}
 
         if self.bearer_auth_credentials_source:
             await self.handle_bearer_auth(headers)

src/confluent_kafka/schema_registry/_sync/schema_registry_client.py

@@ -441,7 +441,7 @@ def send_request(
             body = json.dumps(body)
             headers = {'Content-Length': str(len(body)),
                        'Content-Type': "application/vnd.schemaregistry.v1+json",
-                       'Accept-Version': "8.0"}
+                       'Confluent-Accept-Unknown-Properties': "true"}
 
         if self.bearer_auth_credentials_source:
             self.handle_bearer_auth(headers)