Console.Error should not be referenced in a static object

Changing the Console.Error throws System.ObjectDisposedException

Console.Error can be changed using Console.SetError() method, so having this as a static reference prevents using the "newly" assigned TextWriter as it keeps the referenced to the original instance which has been disposed.

"Cannot write to a closed TextWriter."
at System.IO.StringWriter.Write(String value)
at System.IO.TextWriter.SyncTextWriter.Write(String value)
at CommandLine.Parser.<>c__DisplayClass17_0`1.b__1(IEnumerable`1 _, TextWriter writer)
at CSharpx.MaybeExtensions.Do[T1,T2](Maybe`1 maybe, Action`2 action)
at CommandLine.Parser.<>c__DisplayClass17_0`1.b__0(IEnumerable`1 errors)
at CommandLine.ParserResultExtensions.WithNotParsed[T](ParserResult`1 result, Action`1 action)
at CommandLine.Parser.DisplayHelp[T](ParserResult`1 parserResult, TextWriter helpWriter, Int32 maxDisplayWidth)
at CommandLine.Parser.MakeParserResult[T](ParserResult`1 parserResult, ParserSettings settings)
at CommandLine.Parser.ParseArguments(IEnumerable`1 args, Type[] types)
at TestApp.Program.Main(String[] args) in Program.cs:line 25
at TestApp.Tests.ProgramTest.Main_ShouldExecuteCommandSuccesfully(List`1 args) in ProgramTest.cs:line 18

https://github.com/commandlineparser/commandline/blob/d443a51aeb3a418425e970542b3b96e9da5f62e2/src/CommandLine/Parser.cs#L22

```c#
private static readonly Lazy DefaultParser = new Lazy(() => new Parser(new ParserSettings { HelpWriter = Console.Error }));
```

Start at src/CommandLine/Parser.cs line 22 and inspect how the default parser captures Console.Error. Reproduce the failure by changing Console.Error and disposing the previous writer, then verify that help output uses the newly assigned writer without throwing ObjectDisposedException.

由索引模型根據 Issue 內容生成。