Add workflow to validate project for trimming

Author: MaggieKimani1

.github/workflows/ci-cd.yml

@@ -36,3 +36,18 @@ jobs:
         shell: pwsh
         run: |
           dotnet test Microsoft.OpenApi.sln -c Release -v n
+
+  validate-trimming:
+    name: Validate Project for Trimming
+    runs-on: windows-latest
+    steps:
+      - uses: actions/[email protected]
+
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: 8.x
+
+      - name: Validate Trimming warnings
+        run: dotnet publish -c Release -r win-x64 /p:TreatWarningsAsErrors=true /warnaserror -f net8.0
+        working-directory: ./test/Microsoft.OpenApi.Trimming.Tests