minor #336 Add PHP 8.1 to GitHub actions (DonCallisto)

This PR was merged into the master branch.

Discussion
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Add PHP 8.1 to GitHub actions

As PHP 8.1 will be out shortly and since this bundle claims to support a vast range oh PHP versions, I think it's good to add a build for PHP 8.1 also.

Commits
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ed9b9ef Add PHP 8.1 to GitHub actions

.github/workflows/ci.yaml

@@ -17,6 +17,7 @@ jobs:
                     - '7.3'
                     - '7.4'
                     - '8.0'
+                    - '8.1'
 
         name: PHP ${{ matrix.php }} ${{ matrix.description }}
         steps: