title: Postgres: Password authentication failed for user "user". Role "user" does not exists
body: <p>I'm using Django created with the template cookie-cutter. 
  When I try to run the project with docker locally it gives me the following error.</p>
  
  <blockquote>
    <p>FATAL:  password authentication failed for user "user"<br>
    DETAIL:  Role "user" does not exist.</p>
  </blockquote>
  
  <p>But the role "user" exists. Using the command <code>postgres=# \du</code> gives me the role "user"</p>
  
  <p>I have a <code>.env</code> file with the recommended configuration by cookie cutter.
  <code>POSTGRES_PASSWORD=password
  </code>
  <code>POSTGRES_USER=user</code></p>
  
  <p>I tried giving the user a password and granting all privileges of the database to the user but doesn't work.</p>