Update workflows (#21)

* Failed if uncommited changes
* Fix virtual env
* Fix lint workflow
* Display changes

.github/workflows/uncommited.yml

@@ -12,6 +12,10 @@ jobs:
         # https://github.com/actions/checkout
         name: Checkout
         uses: actions/checkout@v1
+      -
+        # https://github.com/actions/setup-node
+        name: Set up Node
+        uses: actions/setup-node@v1
       -
         name: Build
         run: |
@@ -23,5 +27,7 @@ jobs:
         name: Check for uncommitted changes
         run: |
           if [[ `git status --porcelain` ]]; then
+            git status --porcelain
             echo "##[error] found changed files after build. please 'npm run build && npm run format && npm prune --production'"
+            exit 1
           fi