Fix: Query connection by connectionId instead of pk (or id)

Signed-off-by: George J Padayatti <george.padayatti@igrant.io>

connection/views.py

@@ -149,7 +149,7 @@ def delete(self, request, connectionId):
 
         try:
             connection = Connection.objects.get(
-                pk=connectionId, dataSourceId=datasource
+                connectionId=connectionId, dataSourceId=datasource
             )
             connection.delete()
             return JsonResponse({}, status=status.HTTP_204_NO_CONTENT)