ci: fix nightly run (#339)

Co-authored-by: Barnabas Busa <busa.barnabas@gmail.com>

.github/workflows/nightly.yml

@@ -10,7 +10,7 @@ jobs:
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
     steps:
-      - uses: actions/checkout@4
+      - uses: actions/checkout@v4
       - id: set-matrix
         run: echo "::set-output name=matrix::$(ls ./.github/tests/*.yaml | jq -R -s -c 'split("\n")[:-1]')"
   run_with_args: