optimise drone build

.drone.yml

@@ -4,29 +4,12 @@ type: docker
 name: default
 
 steps:
-- name: qa_main
-  image: python:3.8-alpine
+- name: qa
+  image: registry.wtf-eg.net/ki-backend-builder:1.0.0
   commands:
-  - apk add --no-cache gcc g++ musl-dev python3-dev
-  - pip3 install pipenv
   - pipenv install --dev
   - pipenv run flake8
   - pipenv run python -m unittest discover ki
-  when:
-    branch:
-    - main
-
-- name: qa_pr
-  image: python:3.8-alpine
-  commands:
-  - apk add --no-cache gcc g++ musl-dev python3-dev
-  - pip3 install pipenv
-  - pipenv install --dev
-  - pipenv run flake8
-  - pipenv run python -m unittest discover ki
-  when:
-    event:
-    - pull_request
 
 - name: docker-publish
   image: plugins/docker
@@ -42,3 +25,6 @@ steps:
   when:
     branch:
       - main
+
+image_pull_secrets:
+  - dockerconfigjson