pin golang at 1.16.6

Author: yue9944882

.github/workflows/go.yml

@@ -16,7 +16,7 @@ jobs:
     - name: Set up Go 1.x
       uses: actions/setup-go@v2
       with:
-        go-version: ^1.16
+        go-version: 1.16.6
       id: go
 
     - run: go get github.com/golangci/golangci-lint/cmd/golangci-lint