Resolve "Improve pipeline speed"

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Closes #126 (closed)

build/ci/.build-container.yml

@@ -4,6 +4,7 @@ variables:
 .build: &build
   before_script:
     - echo "override global before script"
+    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
   image: docker:19.03.12
   services:
   - name: docker:19.03.12-dind
@@ -12,21 +13,9 @@ variables:
   tags:
     - dind
   script:
-    - docker build \
-        --cache-from registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache
-        --target builder
-        --build-arg GITLAB_USER=$GO_MODULES_USER \
-        --build-arg GITLAB_TOKEN=$GO_MODULES_ACCESS_TOKEN \
-        --build-arg BUILDARGS=$BUILDARGS \
-        -t registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache .
-    - >
-      docker build \
-        --cache-from registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache
-        --build-arg GITLAB_USER=$GO_MODULES_USER \
-        --build-arg GITLAB_TOKEN=$GO_MODULES_ACCESS_TOKEN \
-        --build-arg BUILDARGS=$BUILDARGS \
-        -t $DOCKER_IMAGE_SHA .
-    - docker login -u gitlab-ci-token -p $CI_JOB_TOKEN $CI_REGISTRY
+    - docker pull registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache
+    - docker build --target builder --build-arg GITLAB_USER=$GO_MODULES_USER --build-arg GITLAB_TOKEN=$GO_MODULES_ACCESS_TOKEN --build-arg BUILDARGS=$BUILDARGS --cache-from registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache -t registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache .
+    - docker build --cache-from registry.code.fbi.h-da.de/cocsn/gosdn:ci_build_cache --build-arg GITLAB_USER=$GO_MODULES_USER --build-arg GITLAB_TOKEN=$GO_MODULES_ACCESS_TOKEN --build-arg BUILDARGS=$BUILDARGS -t $DOCKER_IMAGE_SHA .
     - docker push $DOCKER_IMAGE_SHA
     - docker tag $DOCKER_IMAGE_SHA $TAG
     - docker tag $DOCKER_IMAGE_SHA registry.code.fbi.h-da.de/cocsn/gosdn:${CI_PIPELINE_ID}