chore(ci): update golangci-lint to v2.6

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Co-Authored-By: Claude <noreply@anthropic.com>

Author: appleboy

.github/workflows/go.yml

@@ -23,6 +23,7 @@ jobs:
       - name: Setup golangci-lint
         uses: golangci/golangci-lint-action@v9
         with:
+          version: v2.6
           args: --verbose
   test:
     strategy: