Fix stuck when ffmpeg error in live pipe mux

[ChocoLZS]

Fix the stuck issue mentioned in #468

When ffmpeg exit abnormally, error happend for using RE_LIVE_PIPE_OPTIONS with pipe to ffmepg muxer.

In Windows, beacause of NamedPipeServerStream, the program will exited by C# throwing Exception.
In linux, the Process may not handle the none-zero exit code, so the main thread is still running.

I‘m not an expert at C#, I tryied to log the error message from ffmpeg process, but failed.

---

Command

RE_LIVE_PIPE_OPTIONS="-c copy -f flv rtmp://${url}"  N_m3u8DL-RE "url" --live-real-time-merge --live-pipe-mux

Windows pipe error to ffmpeg

ERROR: System.IO.IOException: Pipe is broken.
   at System.IO.Pipes.PipeStream.Write(Byte[] buffer, Int32 offset, Int32 count)
   at System.IO.Stream.CopyTo(Stream destination, Int32 bufferSize)
   at N_m3u8DL_RE.DownloadManager.SimpleLiveRecordManager2.RecordStreamAsync(StreamSpec streamSpec, ProgressTask task, SpeedContainer speedContainer, BufferBlock`1 source) in N_m3u8DL-RE\src\N_m3u8DL-RE\DownloadManager\SimpleLiveRecordManager2.cs:line 564
   at N_m3u8DL_RE.DownloadManager.SimpleLiveRecordManager2.<>c__DisplayClass28_0.<<StartRecordAsync>b__8>d.MoveNext() in N_m3u8DL-RE\src\N_m3u8DL-RE\DownloadManager\SimpleLiveRecordManager2.cs:line 854
--- End of stack trace from previous location ---
   at System.Threading.Tasks.Parallel.<>c__53`1.<<ForEachAsync>b__53_0>d.MoveNext()
--- End of stack trace from previous location ---
   at N_m3u8DL_RE.DownloadManager.SimpleLiveRecordManager2.<>c__DisplayClass28_0.<<StartRecordAsync>b__1>d.MoveNext() in N_m3u8DL-RE\src\N_m3u8DL-RE\DownloadManager\SimpleLiveRecordManager2.cs:line 850
--- End of stack trace from previous location ---
   at Spectre.Console.Progress.<>c__DisplayClass31_0.<<StartAsync>b__0>d.MoveNext() in /_/src/Spectre.Console/Live/Progress/Progress.cs:line 103
--- End of stack trace from previous location ---
   at Spectre.Console.Progress.<>c__DisplayClass32_0`1.<<StartAsync>b__0>d.MoveNext() in /_/src/Spectre.Console/Live/Progress/Progress.cs:line 138
--- End of stack trace from previous location ---
   at Spectre.Console.Internal.DefaultExclusivityMode.RunAsync[T](Func`1 func) in /_/src/Spectre.Console/Internal/DefaultExclusivityMode.cs:line 40
   at Spectre.Console.Progress.StartAsync[T](Func`2 action) in /_/src/Spectre.Console/Live/Progress/Progress.cs:line 121
   at Spectre.Console.Progress.StartAsync(Func`2 action) in /_/src/Spectre.Console/Live/Progress/Progress.cs:line 101
   at N_m3u8DL_RE.DownloadManager.SimpleLiveRecordManager2.StartRecordAsync() in N_m3u8DL-RE\src\N_m3u8DL-RE\DownloadManager\SimpleLiveRecordManager2.cs:line 811
   at N_m3u8DL_RE.Program.DoWorkAsync(MyOption option) in N_m3u8DL-RE\src\N_m3u8DL-RE\Program.cs:line 410
   at N_m3u8DL_RE.CommandLine.CommandInvoker.<>c__DisplayClass81_0.<<InvokeArgs>b__0>d.MoveNext() in N_m3u8DL-RE\src\N_m3u8DL-RE\CommandLine\CommandInvoker.cs:line 628
--- End of stack trace from previous location ---
   at System.CommandLine.Invocation.AnonymousCommandHandler.InvokeAsync(InvocationContext context)
   at System.CommandLine.Invocation.InvocationPipeline.<>c__DisplayClass4_0.<<BuildInvocationChain>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass17_0.<<UseParseErrorReporting>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass12_0.<<UseHelp>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass22_0.<<UseVersionOption>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass19_0.<<UseTypoCorrections>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<UseSuggestDirective>b__18_0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass16_0.<<UseParseDirective>b__0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<RegisterWithDotnetSuggest>b__5_0>d.MoveNext()
--- End of stack trace from previous location ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass8_0.<<UseExceptionHandler>b__0>d.MoveNext()