Refactor gitlab-ci

- Use gitlab-ci services instead of docker-compose to run postgres and
  redis
- Switch to docker socket

.gitlab-ci.yml

@@ -2,15 +2,15 @@ image: docker:latest
 
 .runner_tags: &runner_tags
   tags:
-    - dind
-
-services:
-  - docker:dind
+    - docker
 
 variables:
   CONTAINER_TEST_IMAGE: "$CI_REGISTRY_IMAGE:$CI_COMMIT_REF_NAME"
   CONTAINER_RELEASE_IMAGE: "$CI_REGISTRY_IMAGE:latest"
   CONTAINER_CACHE_IMAGE: "$CI_REGISTRY_IMAGE:master"
+  POSTGRES_USER: ics
+  POSTGRES_PASSWORD: icspwd
+  POSTGRES_DB: csentry_db_test
 
 stages:
   - build
@@ -32,18 +32,13 @@ build:
 test:
   <<: *runner_tags
   stage: test
-  before_script:
-    - apk add --update py-pip
-    - pip install docker-compose
-    - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
+  image: "$CONTAINER_TEST_IMAGE"
+  services:
+    - postgres:10
+    - redis:4.0
+  before_script: []
   script:
-    - docker pull "$CONTAINER_TEST_IMAGE"
-    - docker-compose -f docker-compose.yml up -d postgres redis
-    - sleep 5
-    - docker-compose -f docker-compose.yml run --rm web
-  after_script:
-    - docker rm -f csentry_postgres
-    - docker rm -f csentry_redis
+    - pytest --cov=app -v
 
 release-image:
   <<: *runner_tags