add GH action

Author: kaspersorensen

.github/workflows/dotnet.yml

@@ -0,0 +1,52 @@
+name: .NET Build & Test
+
+on:
+  push:
+    branches: 
+      - main
+      - github-action
+  pull_request:
+    branches:
+      - main
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: '9.0.x'
+
+      - name: Cache NuGet packages
+        uses: actions/cache@v4
+        with:
+          path: ~/.nuget/packages
+          key: ${{ runner.os }}-nuget-${{ hashFiles('**/*.csproj') }}
+          restore-keys: |
+            ${{ runner.os }}-nuget-
+
+      - name: Restore
+        run: dotnet restore
+
+      - name: Restore .NET tools
+        run: dotnet tool restore
+
+      - name: Build
+        run: dotnet build --configuration Release --no-restore
+
+      - name: Test
+        run: dotnet test --configuration Release --no-build --verbosity normal
+
+