Re-enable PHPStan job

Closes #3415291

.gitlab-ci.yml

@@ -100,20 +100,21 @@ variables:
 #
 ###################################################################################
 
+.extra-variables: &extra-variables
+  - MODULE_DIR=$_WEB_ROOT/modules/custom/$CI_PROJECT_NAME
+  # Strip the `-dev` suffix out of $_TARGET_CORE to reveal the name of the Drupal core branch.
+  - CORE_BRANCH=`echo $_TARGET_CORE | sed -e "s/-dev$//"`
+
 composer:
   extends: .composer-base
   before_script:
     - composer archive --file=module
   after_script:
-    # Ensure the module is physically located within the document root, not just
-    # symlinked from it.
-    - MODULE_DIR=$_WEB_ROOT/modules/custom/$CI_PROJECT_NAME
+    - *extra-variables
     - rm -r -f $MODULE_DIR
     - mkdir -p $MODULE_DIR
     - tar -x -f module.tar -C $MODULE_DIR
     - rm module.tar
-    # Strip the `-dev` suffix out of $_TARGET_CORE to reveal the name of the Drupal core branch.
-    - CORE_BRANCH=`echo $_TARGET_CORE | sed -e "s/-dev$//"`
     - git clone https://git.drupalcode.org/project/drupal.git --depth 1 --branch $CORE_BRANCH /tmp/drupal-core
     - mv /tmp/drupal-core/composer $_WEB_ROOT
 
@@ -124,6 +125,7 @@ phpcs:
 
 phpstan:
   before_script:
+    - *extra-variables
     # Ensure our PHPStan configuration has the correct include path to core's PHPStan configuration.
     - sed -i "s#%rootDir%/../../../#%rootDir%/../../../$_WEB_ROOT/#" $MODULE_DIR/phpstan.neon
     - cat $MODULE_DIR/phpstan.neon