CI: individual caches for pre-commit jobs

CI jobs that call different pre-commit hooks need separate caches because pre-commit installs only those environments that are needed for the current call.

.gitlab-ci.yml

@@ -19,7 +19,6 @@ workflow:
 .colorized:
   variables:
     DEFAULT: '\033[0m'
-    GREEN: '\033[0;32m'
     RED: '\033[0;31m'
 
 .ci_dir:
@@ -27,48 +26,39 @@ workflow:
     CI_GITIGNORE_DIR: ${CI_PROJECT_DIR}/.ci_dir
 
 .common_pre_commit:
-  extends:
-    - .colorized
-    - .ci_dir
+  extends: .ci_dir
   variables:
     APK_CACHE_DIR: ${CI_GITIGNORE_DIR}/apk-cache
     PRE_COMMIT_HOME: ${CI_GITIGNORE_DIR}/pre-commit
-    CACHE_POLICY: pull
   before_script:
     - mkdir -p "${APK_CACHE_DIR}"
     - apk --cache-dir "${APK_CACHE_DIR}" --update-cache add git pre-commit
     - |
       # Clean up cache
-      case ${CACHE_POLICY} in
-        *push) (
-          set -o pipefail
-          apk --cache-dir "${APK_CACHE_DIR}" cache clean
-          python3 --version | diff - "${PRE_COMMIT_HOME}/python_version.txt" 2>/dev/null || {
-            rm -rf "${PRE_COMMIT_HOME}"
-            mkdir -p "${PRE_COMMIT_HOME}"
-            python3 --version > "${PRE_COMMIT_HOME}/python_version.txt"
-          }
-        ) ;;
-        *) printf "${GREEN}Skipped due to policy.\n${DEFAULT}" ;;
-      esac
+      (
+        set -o pipefail
+        apk --cache-dir "${APK_CACHE_DIR}" cache clean
+        python3 --version | diff - "${PRE_COMMIT_HOME}/python_version.txt" 2>/dev/null || {
+          rm -rf "${PRE_COMMIT_HOME}"
+          mkdir -p "${PRE_COMMIT_HOME}"
+          python3 --version > "${PRE_COMMIT_HOME}/python_version.txt"
+        }
+      )
   tags:
     - alpine
   cache:
     - key: apk-pre-commit
       paths:
         - ${APK_CACHE_DIR}
-      policy: ${CACHE_POLICY}
     - key:
+        prefix: ${CI_JOB_NAME_SLUG}
         files:
           - .pre-commit-config.yaml
       paths:
         - ${PRE_COMMIT_HOME}
-      policy: ${CACHE_POLICY}
 
 Check licenses:
   extends: .common_pre_commit
-  variables:
-    CACHE_POLICY: pull
   script:
     - pre-commit run --color=always --hook-stage manual reuse
   rules:
@@ -79,8 +69,6 @@ Check licenses:
 
 Check style:
   extends: .common_pre_commit
-  variables:
-    CACHE_POLICY: pull-push
   script:
     - pre-commit run --show-diff-on-failure --color=always --all-files
   rules: