Merge pull request 'Update actions/checkout action to v6' (#6) from renovate/actions-checkout-6.x into main

Reviewed-on: #6

.gitea/workflows/build.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Check out repository code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           github-server-url: 'https://git.secretmine.de/'
       - name: Login to Registry

.github/workflows/build.yml

@@ -12,7 +12,7 @@ jobs:
       contents: read
     steps:
       - name: Check out repository code
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
       - name: Login to Registry
         uses: docker/login-action@v3
         with: