GetPublishedProcesses() throws the exception when there is the pipe with invalid symbol in system.

Windows x64, .NET Framework 4.7.2 (compatible with .NET Standard 2.0)

Compile and run the following sample:
```
using System;
using System.IO.Pipes;

namespace ConsoleApp45
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
var pipe = new NamedPipeServerStream("some\x0016name");
pipe.WaitForConnection();
}
}
}
```

Stack trace:
```
System.ArgumentException: Illegal characters in path.
at System.IO.Path.CheckInvalidPathChars(String path, Boolean checkAdditional)
at System.IO.Path.IsPathRooted(String path)
at System.IO.Path.CombineNoChecks(String path1, String path2)
at System.IO.StringResultHandler.CreateObject(SearchData searchData, WIN32_FIND_DATA& findData)
at System.IO.FileSystemEnumerableIterator`1.MoveNext()
at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
at System.IO.Directory.GetFiles(String path)
at Microsoft.Diagnostics.NETCore.Client.DiagnosticsClient.<g__GetAllPublishedProcesses|13_0>d.MoveNext()
at System.Linq.Enumerable.d__64`1.MoveNext()
```