Manage environment variables in managed apache airflow

I am using aws managed apache airflow (also called mwaa) and try to set up the aws_key_id and aws_secret with aws_default in the connections. But the mwaa somehow creates an environment variable AIRFLOW_CONN_AWS_DEFAULT that values as aws:// and it will always try to find the credentials from here first instead of in the connections.

So is there a way I can stop aws creating this environment variable by default?