Use latest versions

Author: Greg Bowler

Diff for: .github/workflows/ci.yml

@@ -9,10 +9,10 @@ jobs:
     steps:
       - uses: actions/checkout@v2
 
-      - uses: php-actions/composer@dynamic-docker
+      - uses: php-actions/composer@v5
 
       - name: PHPUnit Tests
-        uses: php-actions/phpunit@dynamic-docker
+        uses: php-actions/phpunit@v2
         with:
           bootstrap: vendor/autoload.php
           configuration: test/phpunit.xml