rc build action fix syntax

.github/workflows/rc-build.yml

@@ -12,7 +12,7 @@ jobs:
       - name: Setup Go
         uses: actions/setup-go@v2
         with: 
-        go-version: '^1.16.0'
+          go-version: '^1.16.0'
 
       - name: grpc
         run: make grpc