update CI

Author: leandrocp

.github/workflows/elixir.yml

@@ -40,6 +40,7 @@ jobs:
       postgres:
         image: postgres:13.1
         env:
+          POSTGRES_USER: postgres
           POSTGRES_PASSWORD: postgres
         options: >-
           --health-cmd pg_isready
@@ -132,12 +133,12 @@ jobs:
 
       - run: mix tailwind.install
 
+      - run: mix compile --warnings-as-errors
+
       - run: mix format --check-formatted
 
       - run: mix deps.unlock --check-unused
 
       - run: mix credo --strict
 
       - run: mix dialyzer
-
-      - run: mix compile --warnings-as-errors