Fix Vault Hook default connection name (#20792)
Fix Vault Hook default connection name (#20792)

HashiCorp Vault connection uses `imap_default` as default connection name, which seems to be a copy/paste error.
nathanielvarona/airflow,bolkedebruin/airflow,nathanielvarona/airflow,bolkedebruin/airflow,Acehaidrey/incubator-airflow,apache/airflow,cfei18/incubator-airflow,danielvdende/incubator-airflow,danielvdende/incubator-airflow,cfei18/incubator-airflow,Acehaidrey/incubator-airflow,cfei18/incubator-airflow,mistercrunch/airflow,nathanielvarona/airflow,bolkedebruin/airflow,cfei18/incubator-airflow,nathanielvarona/airflow,nathanielvarona/airflow,apache/airflow,lyft/incubator-airflow,Acehaidrey/incubator-airflow,mistercrunch/airflow,danielvdende/incubator-airflow,danielvdende/incubator-airflow,Acehaidrey/incubator-airflow,cfei18/incubator-airflow,apache/airflow,lyft/incubator-airflow,bolkedebruin/airflow,nathanielvarona/airflow,apache/airflow,apache/airflow,Acehaidrey/incubator-airflow,cfei18/incubator-airflow,danielvdende/incubator-airflow,danielvdende/incubator-airflow,mistercrunch/airflow,Acehaidrey/incubator-airflow,lyft/incubator-airflow,bolkedebruin/airflow,apache/airflow,lyft/incubator-airflow,mistercrunch/airflow