Address Node.js 12 actions are deprecated.

Message on workflows continued with
For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/.
Please update the following actions to use Node.js 16: actions/checkout@v2

.github/workflows/build-test.yaml

@@ -16,7 +16,7 @@ jobs:
       matrix:
         os: [ fedora-rawhide, fedora-37, fedora-36, fedora-35, centos-stream-8, centos-stream-9 ]
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
       - name: Set the right OS in the Dockerfile
         run: sed -i "s#^FROM.*#FROM $( echo ${{ matrix.os }} | sed 's#^fedora-#registry.fedoraproject.org/fedora:#; s#^centos-stream-#quay.io/centos/centos:stream#;' )#" tests/Dockerfile
       - name: Build image