Create c.yml

.github/workflows/c.yml

@@ -0,0 +1,15 @@
+name: C CI
+
+on:
+  push:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: [macos-latest, ubuntu-latest, windows-latest]
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Test Suite
+      run: make -C ./test/main nocov