Add POSTGRES_HOST_AUTH_METHOD to redash.env

[uskey512]

Postgres stopped working because this PR was merged.

docker-library/postgres#658

Added setting to allow empty passwords.

[kakakakakku]

Thanks.
I will check it soon :)

[kakakakakku]

@uskey512
Thank you for your awesome Pull Request.
It's works good👍

[kakakakakku]

This is my checking note.

Background

Docker image of PostgreSQL decided breaking change about when use it with no password.
See docker-library/postgres#658

Reproduce

Some error occured when exec docker-compose run --rm server create_db.

$ docker-compose run --rm server create_db
Starting redash-hands-on_redis_1    ... done
Starting redash-hands-on_postgres_1 ... done
Traceback (most recent call last):

... snip ...

sqlalchemy.exc.OperationalError: (psycopg2.OperationalError) could not translate host name "postgres" to address: Name or service not known
 (Background on this error at: http://sqlalche.me/e/e3q8)

This Pull Request

Works good 👍

$ docker-compose run --rm server create_db
Creating redash-hands-on_redis_1    ... done
Creating redash-hands-on_postgres_1 ... done

... snip ...

[2020-02-29 13:06:45,513][PID:1][INFO][alembic.runtime.migration] Context impl PostgresqlImpl.
[2020-02-29 13:06:45,514][PID:1][INFO][alembic.runtime.migration] Will assume transactional DDL.
[2020-02-29 13:06:45,548][PID:1][INFO][alembic.runtime.migration] Running stamp_revision  -> e5c7a4e2df4d