Added workflow to perform a build on push to master (#99)

.github/workflows/dotnet.yml

@@ -0,0 +1,21 @@
+name: .NET
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: 7.0.x
+      - name: Restore dependencies
+        run: dotnet restore
+      - name: Build
+        run: dotnet build --no-restore