Addressing Node.js 20 actions are deprecated.

Warning on the run page continued with
The following actions are running on Node.js 20 and may not work
as expected: actions/checkout@v4.
[...]
For more information see:
https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Author: Jan Pazdziora

.github/workflows/test.yaml

@@ -19,7 +19,7 @@ jobs:
           - 5.2
           - "6.0"
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - run: make build DJANGO_VERSION=${{ matrix.django_version }}
       - run: sudo apt update && sudo apt install -y libwww-mechanize-perl libhttp-cookiejar-perl
       - run: echo '127.0.0.5 www keycloak' | sudo tee -a /etc/hosts