chore: update go-version to ^1.21

- Update the `go-version` to `^1.21`

Signed-off-by: Bo-Yi Wu <[email protected]>

Author: appleboy

.github/workflows/go.yml

@@ -15,7 +15,7 @@ jobs:
       - name: Setup go
         uses: actions/setup-go@v3
         with:
-          go-version: '^1.16'
+          go-version: '^1.21'
       - name: Checkout repository
         uses: actions/checkout@v3
       - name: Setup golangci-lint