update go workflow

Added lines to create a directory that was non-existent

.github/workflows/go.yml

@@ -15,6 +15,9 @@ jobs:
       with:
         go-version: 1.12
       id: go
+      
+    - name: Setup GOPATH
+      run: mkdir -p /home/runner/go/bin
 
     - name: Check out code into the Go module directory
       uses: actions/checkout@v1