PrinterSettings.SupportsColor property is broken

[Documentation](https://docs.microsoft.com/en-us/dotnet/api/system.drawing.printing.printersettings.supportscolor?view=netframework-4.8) claims that `SupportsColor` property :

> Gets a value indicating whether this printer supports color printing.

This is not accurate. This [property](https://github.com/dotnet/runtime/blob/1cf033de96a38b286c07b8311edd5f2eabcfb462/src/libraries/System.Drawing.Common/src/System/Drawing/Printing/PrinterSettings.Windows.cs#L516-L522) P/Invokes [GetDeviceCaps(BITSPIXEL..)](https://docs.microsoft.com/en-us/windows/win32/api/wingdi/nf-wingdi-getdevicecaps), which returns:

> Number of adjacent color bits for each pixel.

It does not take into account "color planes" or gray-scale rendering. I would not recommend using this API in .NET Framework. However in .NET Core 5, we fixed it(issue #34630). I think we should publish a workaround in the docs:

```
using System;
using System.Drawing.Printing;
using System.Runtime.InteropServices;

namespace ConsoleApp1
{
class Program
{
static void Main(string[] _)
{
PrinterSettingsTest();
}

static void PrinterSettingsTest()
{
var document = new PrintDocument();
foreach (string name in PrinterSettings.InstalledPrinters)
{
document.PrinterSettings.PrinterName = name;
Console.WriteLine($"{name} SupportsColor = {document.PrinterSettings.SupportsColor}");
var capability = GetColorDeviceCapability(name);
Console.WriteLine($"\tDeviceCapabilities(DC_COLORDEVICE) returns {capability}");
}

Console.ReadLine();
}

[DllImport("winspool.drv", SetLastError = true, CharSet = CharSet.Unicode, ExactSpelling = true)]
private static extern int DeviceCapabilitiesW(string pDevice, string pPort, short fwCapabilities, IntPtr pOutput, IntPtr pDevMode);
private const short DC_COLORDEVICE = 32;

private static bool GetColorDeviceCapability(string printerName)
{
return DeviceCapabilitiesW(printerName, null, DC_COLORDEVICE, IntPtr.Zero, IntPtr.Zero) == 1;
}
}
}
```