Merge pull request #120 from softwaremill/renovate/actions-checkout-6.x

Update actions/checkout action to v6

Author: lukaszlenart

.github/workflows/ci.yaml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+        uses: actions/checkout@1af3b93b6815bc44a9784bd300feb67ff0d1eeb3 # v6
       - name: Setup JDK
         uses: actions/setup-java@v5
         with: