Merge pull request #286 from elifesciences/renovate/actions-checkout-5.x

Update actions/checkout action to v5

Author: scottaubrey

.github/workflows/ci.yaml

@@ -18,6 +18,6 @@ jobs:
       matrix:
         php_version: ["7.1", "7.2", "7.3", "7.4", "8.0", "8.1", "8.2", "8.3"]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
       - name: Run tests
         run: make PHP_VERSION=${{ matrix.php_version }} test-ci