Create checks.yml

Author: mac-cain13

.github/workflows/checks.yml

@@ -0,0 +1,15 @@
+name: Checks
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: '*'
+
+jobs:
+  build:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Build
+      run: swift build -v