Integrate gitlab-ci/report_image_changes_in_mr

--

Commit: seco-ne/yocto/infrastructure/gitlab-ci@1299a9d6

CI: add "report-image-diff" job

Add a python script and a GitLab CI job to run it. The job is triggered
when the build is complete.

The script retrieves build artifacts for the default/main branch
(currently "kirkstone") in the manifest repo and build artifacts
for the integration branch of merge request.

After that, it compares those builds and creates a summary of the overall
changes. In particular:
- size of compressed artifacts (artifacts.zip)
- size of built image
- difference between manifest files

The summary is reported to stdout and as a comment to the merge request.
Each run of the pipeline means removing the old summary comment and
creating a new one when the build is finished.

.gitlab-ci @ 1299a9d6

-Subproject commit dcc8d92b38fde9c4feb2268eefdf7b68b25bc25b
+Subproject commit 1299a9d671826104a620e4b2fd8ce278dd306987

.gitlab-ci.yml

@@ -4,9 +4,9 @@
 # ---------------------------------------------------------------------------------------
 include:
   - project: '${CI_PROJECT_ROOT_NAMESPACE}/yocto/infrastructure/gitlab-ci'
-    ref: dcc8d92b38fde9c4feb2268eefdf7b68b25bc25b
+    ref: 1299a9d671826104a620e4b2fd8ce278dd306987
     file: 'manifest-integration.yml'
 
 variables:
-  GITLAB_CI_REVISION: dcc8d92b38fde9c4feb2268eefdf7b68b25bc25b
+  GITLAB_CI_REVISION: 1299a9d671826104a620e4b2fd8ce278dd306987
   BB_RECIPE_NAME: ilitek