ci: only use requested images; enable opcache; preload npm

Author: jrchamp

.github/workflows/ci.yml

@@ -8,7 +8,7 @@ jobs:
 
     services:
       postgres:
-        image: postgres:15
+        image: ${{ matrix.database == 'pgsql' && 'postgres:16' || '' }}
         env:
           POSTGRES_USER: 'postgres'
           POSTGRES_HOST_AUTH_METHOD: 'trust'
@@ -17,7 +17,7 @@ jobs:
         options: --health-cmd pg_isready --health-interval 10s --health-timeout 5s --health-retries 3
 
       mariadb:
-        image: mariadb:10
+        image: ${{ matrix.database == 'mariadb' && 'mariadb:10' || '' }}
         env:
           MYSQL_USER: 'root'
           MYSQL_ALLOW_EMPTY_PASSWORD: "true"
@@ -52,7 +52,7 @@ jobs:
 
     steps:
       - name: Check out repository code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           path: plugin
 
@@ -61,7 +61,8 @@ jobs:
         with:
           php-version: ${{ matrix.php }}
           extensions: ${{ matrix.extensions }}
-          ini-values: max_input_vars=5000
+          ini-values: max_input_vars=5000, opcache.enable_cli=1, opcache.file_cache=/tmp/, opcache.validate_timestamps=0
+
           # If you are not using code coverage, keep "none". Otherwise, use "pcov" (Moodle 3.10 and up) or "xdebug".
           # If you try to use code coverage with "none", it will fallback to phpdbg (which has known problems).
           coverage: none
@@ -83,6 +84,11 @@ jobs:
           sudo locale-gen en_AU.UTF-8
           echo "NVM_DIR=$HOME/.nvm" >> $GITHUB_ENV
 
+      - name: Preload node from local
+        uses: actions/setup-node@v6
+        with:
+          node-version: 'lts/jod'
+
       - name: Install moodle-plugin-ci
         id: install_ci
         run: |