Add nuget publish action

.github/workflows/nuget.yml

@@ -0,0 +1,31 @@
+# This workflow will build a .NET project
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-net
+
+name: .NET
+
+on:
+  push:
+    branches: [ "master" ]
+
+jobs:
+  publish:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+      with:
+        fetch-depth: 0
+    - name: Setup .NET
+      uses: actions/setup-dotnet@v3
+      with:
+        dotnet-version: 8.0.x
+    - name: Pack
+      working-directory: ./Source/SharpNeedle
+      run: dotnet pack
+    - name: Publish
+      working-directory: ./Source/SharpNeedle
+      run: dotnet nuget push **/*.nupkg -s $NUGET_SOURCE -k $NUGET_AUTH_TOKEN --skip-duplicate
+      env:
+        NUGET_AUTH_TOKEN: ${{ secrets.NUGET_TOKEN }}
+        NUGET_SOURCE: https://api.nuget.org/v3/index.json