[docker-compose]: Fix issue about migration to postgresql 12

[Ankirama]

From postgresql 11 or 12, we can't use an empty password by default.

You may:

• Define a password (POSTGRES_PASSWORD)
• Set trust as auth method (POSTGRES_HOST_AUTH_METHOD=trust)

The easiest way to fix it right is to use the trust auth method, but it should be better in a production environment to set a password instead.

Thank you for your work.

[ku1ik]

Thanks!