minor #982 Use PHP 8.5 for PHPStan checks in CI (OskarStark)

This PR was merged into the main branch.

Discussion
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 Use PHP 8.5 for PHPStan checks in CI

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Docs?         | no
| Issues        | --
| License       | MIT

Commits
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45b608b Use PHP 8.5 for PHPStan checks in CI

Author: OskarStark

.github/workflows/code-quality.yaml

@@ -21,7 +21,7 @@ jobs:
         strategy:
             fail-fast: false
             matrix:
-                php-version: [ '8.4' ]
+                php-version: [ '8.5' ]
         steps:
             - name: Checkout
               uses: actions/checkout@v6