Github actions: run PHPUnit tests on PHP 8.0 to 8.5

Author: jdpanderson

.github/workflows/ci.yml

@@ -5,6 +5,10 @@ on: [push]
 jobs:
   build-test:
     runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        php-versions: ['8.0', '8.1', '8.2', '8.3', '8.4', '8.5']
 
     steps:
       - uses: actions/checkout@v3