Update test image build

Use the release image as the base image for the test image build. This
will decrease the build time as only the exposure and env need to be
set.

.gitlab-ci.yml

@@ -240,7 +240,7 @@ django-tests:
         coverage_format: cobertura
         path: .tools/coverage/coverage.xml
 
-build_test:
+build_nginx:
   stage: build
   extends:
     - .build
@@ -253,9 +253,10 @@ build_test:
         $KANIKO_ARGS
         $KANIKO_CACHE_ARGS
         --dockerfile $CI_PROJECT_DIR/Dockerfile
-        --destination $CI_REGISTRY_IMAGE/ci/hub:ci-$CI_PIPELINE_ID-test
+        --target nginx
+        --destination $CI_REGISTRY_IMAGE/ci/nginx:ci-$CI_PIPELINE_ID
 
-build_nginx:
+build_release:
   stage: build
   extends:
     - .build
@@ -268,24 +269,27 @@ build_nginx:
         $KANIKO_ARGS
         $KANIKO_CACHE_ARGS
         --dockerfile $CI_PROJECT_DIR/Dockerfile
-        --target nginx
-        --destination $CI_REGISTRY_IMAGE/ci/nginx:ci-$CI_PIPELINE_ID
+        --target webworker
+        --destination $CI_REGISTRY_IMAGE/ci/hub:ci-$CI_PIPELINE_ID
 
-build_release:
+build_test:
   stage: build
   extends:
     - .build
   needs:
-    - generate_css
-    - migration_check
-    - django-tests
+    - build_release
   script:
+    - |
+      cat > Dockerfile_Test <<EOF
+        FROM $CI_REGISTRY_IMAGE/ci/hub:ci-$CI_PIPELINE_ID
+        ENV BIND_HTTP=1
+        EXPOSE 8000
+      EOF
     - /kaniko/executor
+        --destination $CI_REGISTRY_IMAGE/ci/hub:ci-$CI_PIPELINE_ID-test
         $KANIKO_ARGS
         $KANIKO_CACHE_ARGS
-        --dockerfile $CI_PROJECT_DIR/Dockerfile
-        --target webworker
-        --destination $CI_REGISTRY_IMAGE/ci/hub:ci-$CI_PIPELINE_ID
+        --dockerfile Dockerfile_Test
 
 .test_image:
   extends: