ci: update GitHub workflows and improve linting configuration

- Update golangci-lint-action from version 4 to version 6 in GitHub workflow

Signed-off-by: appleboy <[email protected]>

Author: appleboy

.github/workflows/testing.yml

@@ -20,7 +20,7 @@ jobs:
         run: make embedmd
 
       - name: check golangci-lint
-        uses: golangci/golangci-lint-action@v4
+        uses: golangci/golangci-lint-action@v6
         with:
           version: latest
           args: --verbose