Proj0036: Remove None when redundant

A <None> project item can be used to represent a file that should have no role in the build process. Hence, removing it after it has been added, for instance because its type has been changed to <Content> or <EmbeddedResource> will have no influence on either the build process, or how the file is displayed in the IDE.

Non-compliant

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
  </PropertyGroup>
  
  <ItemGroup>
    <None Include="*.md" />
    <None Remove="LICENSE.md" />
  </ItemGroup>

  <ItemGroup>
    <EmbeddedResource Remove="LICENSE.md" />
  </ItemGroup>

</Project>

Compliant

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
  </PropertyGroup>
  
  <ItemGroup>
    <None Include="*.md" />
  </ItemGroup>

  <ItemGroup>
    <EmbeddedResource Remove="LICENSE.md" />
  </ItemGroup>

</Project>

Or, when hiding was intended:

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
  </PropertyGroup>
  
  <ItemGroup>
    <None Include="*.md" />
    <None Update="LICENSE.md" Visible="true" />
  </ItemGroup>

</Project>