add publish action

.github/workflows/dotnet.yml

@@ -23,3 +23,31 @@ jobs:
       run: dotnet build Source --no-restore
     - name: Test
       run: dotnet test Source\RetryableAssertions.Tests\RetryableAssertions.Tests.csproj --no-build --verbosity normal
+
+  publish:
+    runs-on: windows-2019
+    needs: test
+    if: github.ref_type == 'tag'
+    steps:
+      - uses: actions/checkout@v3
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v3
+        with:
+          dotnet-version: 6.0.x
+      - name: Restore dependencies
+        run: dotnet restore Source
+      - name: Build
+        run: dotnet build Source --no-restore
+      - name: Pack dotnet
+        run: dotnet pack --configuration Release Source
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v3
+        with:
+          path: "**/*.nupkg"
+          if-no-files-found: error
+      - name: Publish NuGet
+        run: dotnet nuget push "**/*.nupkg" --source https://api.nuget.org/v3/index.json --no-symbols --api-key $env:NUGET_API_KEY
+        env:
+          NUGET_API_KEY: ${{ secrets.NUGET_API_KEY }}
+
+