Move everything not related to a job to general

.gitlab-ci.yml

-stages:
-  - test
-  - build
-  - deploy
-
 include:
     - local: "/ci/general.yml"
     - local: "/ci/test.yml"

ci/build_docker.yml

-image: registry.edugit.org/teckids/team-sysadmin/docker-images/python-pimped:master
-
 build_docker:
   stage: build
   image:

ci/general.yml

+image: registry.edugit.org/teckids/team-sysadmin/docker-images/python-pimped:latest
+
+stages:
+  - test
+  - build
+  - deploy
+
 variables:
   GIT_SUBMODULE_STRATEGY: recursive
   PIP_CACHE_DIR: "$CI_PROJECT_DIR/.cache/pip"