Update shivammathur/setup-php action to v2.26.0

Author: renovate[bot]

.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
         uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
 
       - name: Setup PHP
-        uses: shivammathur/setup-php@2.25.5
+        uses: shivammathur/setup-php@2.26.0
         with:
           php-version: ${{ matrix.php }}
           coverage: xdebug