Log migrations info in consistent way

[kaxil]

same as #13458 but for 82b7c48c147f_remove_can_read_permission_on_config_.py migration

This migration changes logging handlers
so each next migration is differently formatted when doing
airflow db reset. This commit fixes this behavior.

Before:

INFO  [alembic.runtime.migration] Running upgrade 849da589634d -> 2c6edca13270, Resource based permissions.
INFO  [alembic.runtime.migration] Running upgrade 2c6edca13270 -> 61ec73d9401f, Add description field to connection
INFO  [alembic.runtime.migration] Running upgrade 61ec73d9401f -> 64a7d6477aae, fix description field in connection to be text
INFO  [alembic.runtime.migration] Running upgrade 64a7d6477aae -> e959f08ac86c, Change field in DagCode to MEDIUMTEXT for MySql
INFO  [alembic.runtime.migration] Running upgrade e959f08ac86c -> 82b7c48c147f, Remove can_read permission on config resource for User and Viewer role
[2021-02-09 19:17:31,307] {migration.py:555} INFO - Running upgrade 82b7c48c147f -> 449b4072c2da, Increase size of connection.extra field to handle multiple RSA keys
Upgrades done
root@78916ec8c0e5:/opt/airflow# exit

After:

INFO  [alembic.runtime.migration] Running upgrade 849da589634d -> 2c6edca13270, Resource based permissions.
[2021-02-09 19:17:24,539] {manager.py:727} WARNING - No user yet created, use flask fab command to do it.
INFO  [alembic.runtime.migration] Running upgrade 2c6edca13270 -> 61ec73d9401f, Add description field to connection
INFO  [alembic.runtime.migration] Running upgrade 61ec73d9401f -> 64a7d6477aae, fix description field in connection to be text
INFO  [alembic.runtime.migration] Running upgrade 64a7d6477aae -> e959f08ac86c, Change field in DagCode to MEDIUMTEXT for MySql
INFO  [alembic.runtime.migration] Running upgrade e959f08ac86c -> 82b7c48c147f, Remove can_read permission on config resource for User and Viewer role
INFO  [alembic.runtime.migration] Running upgrade 82b7c48c147f -> 449b4072c2da, Increase size of connection.extra field to handle multiple RSA keys
Upgrades done
root@78916ec8c0e5:/opt/airflow# exit

---

^ Add meaningful description above

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