Automatically applying Roslyn code fixes during build

AutoFix.feature

Feature: AutoFix
  Applies code fixes during build

  Scenario: Can apply StyleCop code fix automatically
    Given Foo.csproj =
"""
<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <LangVersion>Latest</LangVersion>
        <TargetFramework>netstandard2.0</TargetFramework>
        <RestoreSources>$(TEMP)\packages;https://api.nuget.org/v3/index.json</RestoreSources>
    </PropertyGroup>
    <ItemGroup>
        <PackageReference Include="AutoCodeFix" Version="*" />
        <PackageReference Include="xunit" Version="2.4.0" />
        <PackageReference Include="StyleCop.Analyzers" Version="1.1.0-beta*" />
    </ItemGroup>
    <ItemGroup>
        <!-- System usings should go first --> 
        <AutoFix Include="SA1208" />
        <!-- Blank line required before single-line comment -->
        <AutoFix Include="SA1515" />
    </ItemGroup>
</Project>
"""
    And Class1.cs = 
"""
using Xunit;
using System;

public static class Program
{
    public static async void Main()
    {
        Console.WriteLine("Hello");
        // This comment is too tight
        Console.ReadLine();
    }
}
"""
    When restoring packages
    And building project
    Then build succeeds
    And Class1.cs = 
"""
using System;
using Xunit;

public static class Program
{
    public static async void Main()
    {
        Console.WriteLine("Hello");

        // This comment is too tight
        Console.ReadLine();
    }
}
"""