Add a workflow

```yaml
# 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: [ "main" ]
pull_request:
branches: [ "main" ]

jobs:
build:

runs-on: ubuntu-latest

steps:
- uses: actions/checkout@v4
- name: Setup .NET
uses: actions/setup-dotnet@v4
with:
dotnet-version: 8.0.x
- name: Restore dependencies
run: dotnet restore
- name: Build
run: dotnet build --no-restore
- name: Test
run: dotnet test --no-build --verbosity normal
```