tests(github): Switch testing to Drupal core 9.2.x (drupal-graphql#1215)

Author: klausi

.github/workflows/testing.yml

@@ -14,7 +14,7 @@ jobs:
       fail-fast: false
       matrix:
         php-versions: ['7.3', '7.4', '8.0']
-        drupal-core: ['9.1.x']
+        drupal-core: ['9.2.x']
         include:
           # Extra run to also test on latest Drupal 8 and PHP 7.2.
           - php-versions: '7.2'

phpstan.neon

@@ -43,6 +43,9 @@ parameters:
       #^Call to deprecated method toInt\\(\\) of class Drupal\\\\Component\\\\Utility\\\\Bytes\\:
       in drupal\\:9\\.1\\.0 and is removed from drupal\\:10\\.0\\.0\\. Use \\\\Drupal\\\\Component\\\\Utility\\\\Bytes\\:\\:toNumber\\(\\) instead$#
       """
+    - """
+      #^Call to deprecated function file_munge_filename\\(\\)#
+      """
     # Drupal allows object property access to custom fields, so we cannot fix
     # that.
     - "#^Property Drupal\\\\.+ \\(Drupal\\\\Core\\\\Field\\\\FieldItemListInterface\\) does not accept .+\\.$#"