Fix setting node version in workflow

.github/workflows/main.yml

@@ -17,7 +17,7 @@ jobs:
     - name: Install Nodejs
       uses: actions/setup-node@v1
       with: 
-        go-version: 10.x
+        node-version: '10.x'
     - name: Install circom
       run: npm install -g circom
     - name: Install snarkjs