Update actions/checkout action to v4 (#75)

.github/workflows/release.yaml

@@ -20,7 +20,7 @@ jobs:
       - name: Check if tag belongs to main branch
         if: endsWith(github.ref, 'main') == false
         run: exit -1
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           # Allow goreleaser to access older tag information.
           fetch-depth: 0