Bump shivammathur/setup-php from 2.19.1 to 2.20.1

Bumps [shivammathur/setup-php](https://github.com/shivammathur/setup-php) from 2.19.1 to 2.20.1.
- [Release notes](https://github.com/shivammathur/setup-php/releases)
- [Commits](https://github.com/shivammathur/setup-php/compare/2.19.1...2.20.1)

---
updated-dependencies:
- dependency-name: shivammathur/setup-php
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/phpunit.yml

@@ -62,7 +62,7 @@ jobs:
           path: apps/${{ env.APP_NAME }}
 
       - name: Set up php ${{ matrix.php-versions }}
-        uses: shivammathur/setup-php@2.19.1
+        uses: shivammathur/setup-php@2.20.1
         with:
           php-version: ${{ matrix.php-versions }}
           tools: phpunit