EnforceCodeStyleInBuild causes IDExxxx diagnostics to be duplicated

[rudism]

Environment

Running Void Linux, using the omnisharp-linux-x64-net6.0.zip package, launched by the neovim-lspconfig plugin.

Tested with both v1.39.12 and v1.39.13-beta.9.

$ dotnet --version
8.0.401
$ dotnet --list-sdks
8.0.401 [/home/rudism/dotnet/sdk]

Reproduce

Generate a new console project:

$ mkdir test
$ cd test
$ dotnet new console

Create a new omnisharp.json file enabling analyzers:

{
  "RoslynExtensionsOptions": {
    "enableAnalyzersSupport": true
  }
}

Edit Program.cs and do something that creates an IDExxxx diagnostic message (for example put a space somewhere it doesn't belong), observe a single diagnostic message:

Now edit the test.csproj file and add <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild> to the top PropertyGroup:

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

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
    <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
  </PropertyGroup>

</Project>

Now edit Program.cs and observe the diagnostic message is duplicated:

Expected Behavior

It shouldn't be showing the same diagnostic messages twice even when enforcing code style analysis during the build.