Add CI for main branch

.github/workflows/backend-build.yml

@@ -0,0 +1,30 @@
+name: Build & Test
+
+on:
+    push:
+        branches:
+        - main
+    pull_request:
+        branches:
+        - main
+
+env:
+    DOTNET_VERSION: '8.0.x'
+
+jobs:
+    build:
+        runs-on: ubuntu-latest
+        steps:
+        - uses: actions/checkout@v3
+        - name: Setup .NET
+          uses: actions/setup-dotnet@v3
+          with:
+            dotnet-version: ${{ env.DOTNET_VERSION }}
+        - name: Install dependencies
+          run: dotnet restore
+
+        - name: Build
+          run: dotnet build --configuration Release --no-restore
+
+        - name: Test
+          run: dotnet test --configuration Realese --no-build