Switch to GH Actions (#13)

Remove appveyor.yml and add GitHub Action yml.

.github/workflows/dotnet.yml

@@ -0,0 +1,30 @@
+name: .Net Build
+
+on:
+  pull_request:
+
+  push:
+    branches:
+     - master
+     tags:
+      - '*'
+
+env:
+  DOTNET_SKIP_FIRST_TIME_EXPERIENCE: 1
+  DOTNET_CLI_TELEMETRY_OPTOUT: 1
+
+jobs:
+  build:
+    name: Github Actions Build
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v4
+      with:
+        dotnet-version: 8.*
+    - name: Build Reason
+          run: echo ${{github.ref}} and ${{github.event_name}}
+    - name: Build
+      run: dotnet build --configuration Release --nologo