Fix errors upgrading from Airflow 1.10.15 (#18573)
Fix errors upgrading from Airflow 1.10.15 (#18573)

If either of those checks failed the session was left in a transaction
with a failure so couldn't be used for future tests.

And the second check (conn_type_null) _always_ failed on 1.10.15,
because even thought the table existed, the `description` column which
the model expects hasn't yet been added (because we are running this pre
migration!) so the fix there is to just select `conn_id` column.
mistercrunch/airflow,nathanielvarona/airflow,apache/airflow,bolkedebruin/airflow,Acehaidrey/incubator-airflow,apache/incubator-airflow,nathanielvarona/airflow,lyft/incubator-airflow,apache/airflow,lyft/incubator-airflow,mistercrunch/airflow,Acehaidrey/incubator-airflow,bolkedebruin/airflow,nathanielvarona/airflow,danielvdende/incubator-airflow,cfei18/incubator-airflow,lyft/incubator-airflow,bolkedebruin/airflow,bolkedebruin/airflow,apache/incubator-airflow,Acehaidrey/incubator-airflow,nathanielvarona/airflow,cfei18/incubator-airflow,mistercrunch/airflow,Acehaidrey/incubator-airflow,apache/airflow,Acehaidrey/incubator-airflow,danielvdende/incubator-airflow,Acehaidrey/incubator-airflow,danielvdende/incubator-airflow,nathanielvarona/airflow,cfei18/incubator-airflow,cfei18/incubator-airflow,cfei18/incubator-airflow,apache/incubator-airflow,danielvdende/incubator-airflow,danielvdende/incubator-airflow,mistercrunch/airflow,apache/airflow,apache/incubator-airflow,cfei18/incubator-airflow,lyft/incubator-airflow,nathanielvarona/airflow,bolkedebruin/airflow,apache/airflow,danielvdende/incubator-airflow,apache/airflow