Proj0047: Label item groups that disable compilation items

There are use cases where a build item should not be treated as a compilation item. However, to prevent this from happening unintentionally (drag and drop in Visual Studio can result to this), the <ItemGroup> containing a

` should be labeled with a description.

Non-compliant

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

  <PropertyGroup>
    <TargetFramework>net9.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup>
    <Compile Remove="Templates/*.cs" />
  </ItemGroup>

</Project>

Compliant

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

  <PropertyGroup>
    <TargetFramework>net9.0</TargetFramework>
  </PropertyGroup>

  <ItemGroup Label="Code templates">
    <Compile Remove="Templates/*.cs" />
  </ItemGroup>

</Project>