Try to fix docker-postgres tests

tox.ini

@@ -10,7 +10,7 @@ whitelist_externals =
     sh
     docker-compose
 commands_pre =
-    docker-compose up --detach mysql redis rabbitmq
+    docker-compose up --detach mysql postgres redis rabbitmq
     pip install --no-deps -r {toxinidir}/requirements/dev.txt
     pip install --no-deps -r {toxinidir}/requirements/common.txt
 commands =
@@ -55,7 +55,7 @@ whitelist_externals=
 commands_pre =
     docker-compose build
 commands =
-    docker-compose run -e TREEHERDER_DEBUG=False -e DATABASE_URL=psql://postgres:mozilla1234@localhost/treeherder backend bash -c "pytest --cov --cov-report=xml tests/ --runslow -p no:unraisableexception"
+    docker-compose run -e TREEHERDER_DEBUG=False -e DATABASE_URL=psql://postgres:mozilla1234@postgres:5432/treeherder backend bash -c "pytest --cov --cov-report=xml tests/ --runslow -p no:unraisableexception"
 
 [flake8]
 per-file-ignores = treeherder/model/models.py:E402