Bump shivammathur/setup-php from 2.10.0 to 2.11.0 (#21)

Bumps [shivammathur/setup-php](https://github.com/shivammathur/setup-php) from 2.10.0 to 2.11.0.
- [Release notes](https://github.com/shivammathur/setup-php/releases)
- [Commits](shivammathur/setup-php@2.10.0...ed61605)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/run-tests.yml

@@ -19,7 +19,7 @@ jobs:
               uses: actions/checkout@v2.3.4
 
             - name: Setup PHP
-              uses: shivammathur/setup-php@2.10.0
+              uses: shivammathur/setup-php@2.11.0
               with:
                   php-version: ${{ matrix.php }}
                   extensions: mbstring