add .cache to .gitignore && .gitlab-ci.yml imported from gist

.gitignore

@@ -11,3 +11,4 @@ keys.txt.asc
 .jekyll-cache
 vendor/
 *_original
+.cache/**

.gitlab-ci.yml

@@ -0,0 +1,20 @@
+# SPDX-FileCopyrightText: 2023 Aminda Suomalainen <suomalainen+git@mikaela.info>
+#
+# SPDX-License-Identifier: CC0-1.0
+
+# Based on https://pre-commit.com
+image: python:alpine
+gitlab-ci-pre-commit:
+  stage: build
+  before_script:
+    - apk add --no-cache git gcc musl-dev go exiftool
+    - pip install pre-commit
+  script:
+    - pre-commit run --all-files --show-diff-on-failure
+  variables:
+    # Remember to gitignore .cache/**
+    PRE_COMMIT_HOME: ${CI_PROJECT_DIR}/.cache/pre-commit
+    TERM: dumb
+  cache:
+    paths:
+      - ${PRE_COMMIT_HOME}