add format check as explicit workflow

.github/workflows/format.yml

@@ -0,0 +1,36 @@
+name: Build and test
+
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+      - staging
+      - trying
+
+jobs:
+  build:
+    name: Test
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        os: ubuntu-latest
+        rust: [nightly]
+        include:
+          - os: ubuntu-latest
+            rust: 'nightly'
+            components: 'rustfmt'
+            targets: 'x86_64-unknown-linux-gnu'
+
+
+    steps:
+      - uses: hecrj/setup-rust-action@v1.3.1
+        with:
+          rust-version: ${{ matrix.rust }}
+          components: ${{ matrix.components || '' }}
+          targets: ${{ matrix.targets || '' }}
+      - name: Checkout
+        uses: actions/checkout@v1
+      - name: Check Formatting
+        run: cargo fmt -- --check