Run pre-commit checks in Gitlab-CI

.gitlab-ci.yml

+variables:
+  TARGET_BRANCH: master
+
+run-checks:
+  image: python:3.9
+  variables:
+    PRE_COMMIT_HOME: ${CI_PROJECT_DIR}/.cache/pre-commit
+  cache:
+    key: "$CI_JOB_NAME-$CI_COMMIT_REF_SLUG"
+    paths:
+      - ${CI_PROJECT_DIR}/.cache
+  script:
+    - python -m venv .cache/pre-commit-venv
+    - . .cache/pre-commit-venv/bin/activate
+    - pip install pre-commit
+    - pre-commit --version
+    - git fetch origin master
+    - pre-commit run --from-ref FETCH_HEAD --to-ref HEAD

.pre-commit-config.yaml

@@ -5,6 +5,9 @@ repos:
   - id: check-yaml
     # this is needed to allow custom classes in YAML
     entry: check-yaml --unsafe
+    files: '.*.yml(/.*)?'
+    exclude: '/IOVs$'
+    types: [file]
   - id: end-of-file-fixer
   - id: trailing-whitespace
   - id: check-merge-conflict