"Unmerged change from project" after running dotnet format

When starting with a piece of code like this where I purposely set the if condition all in one line:

```csharp
public static OptionsBuilder AddOptionsValue(this IServiceCollection services, IConfiguration configuration)
where T : class, new()
{
if (services is null) { throw new ArgumentNullException(nameof(services)); }

return services
.AddOptions()
.Bind(configuration)
.AddOptionsValue();
}
```

After running dotnet format I get the following:

```csharp
public static OptionsBuilder AddOptionsValue(this IServiceCollection services, IConfiguration configuration)
where T : class, new()
{

/* Unmerged change from project 'DotNet.Sdk.Extensions(net5.0)'
Before:
if (services is null) { throw new ArgumentNullException(nameof(services)); }
After:
if (services is null)
{
throw new ArgumentNullException(nameof(services)); }
*/

/* Unmerged change from project 'DotNet.Sdk.Extensions(net6.0)'
Before:
if (services is null) { throw new ArgumentNullException(nameof(services)); }
After:
if (services is null)
{
throw new ArgumentNullException(nameof(services)); }
*/
if (services is null)
{
throw new ArgumentNullException(nameof(services));
}

return services
.AddOptions()
.Bind(configuration)
.AddOptionsValue();
}
```

I seem to be able to reproduce this reliable from [this repo of mine](https://github.com/edumserrano/dotnet-sdk-extensions). The file I changed and mention in this example was this one: [OptionsBuilderExtensions.cs](https://github.com/edumserrano/dotnet-sdk-extensions/blob/4223234b3678447f479c7f07179ab0d24b161270/src/DotNet.Sdk.Extensions/Options/OptionsBuilderExtensions.cs).

The [project](https://github.com/edumserrano/dotnet-sdk-extensions/blob/main/src/DotNet.Sdk.Extensions/DotNet.Sdk.Extensions.csproj) where this happens targets multiple frameworks: `netcoreapp3.1;net5.0;net6.0`.

The `dotnet format` command my GitHub workflow is running looks like the following:
```
dotnet format ${{ github.workspace }}/DotNet.Sdk.Extensions.sln `
--severity info `
--verbosity diagnostic `
--report ${{ env.DOTNET_FORMAT_REPORT_FILEPATH }}
```

This seems related with #1574 .

Hopefully this provides enough information to be able to replicate the issue. Let me know if you need more info.