chore: update actions

Signed-off-by: Vincent Koppen <[email protected]>

Author: vincentkoppen

.github/workflows/citations.yml

@@ -30,6 +30,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
     - name: checkout
-      uses: actions/checkout@v4
+      uses: actions/checkout@v5
+
     - name: Validate CITATION.cff
       uses: dieghernan/cff-validator@v4