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Debugging Blazor WASM in VS Code leaves process behind when finished

See original GitHub issue

Describe the bug

When debugging Blazor WASM 3.2 preview 3 in VS Code and Chrome there is a process left behind after you stop debugging that prevents a subsequent debugging run as it still has ports 5000 and 5001 reserved.

To Reproduce

Create a new Blazor WASM project. Debug it following the instructions on the blog here:

https://devblogs.microsoft.com/aspnet/blazor-webassembly-3-2-0-preview-3-release-now-available

Stop debugging.

Attempt to start a new debugging session.

Error in debug window:

crit: Microsoft.AspNetCore.Server.Kestrel[0]
      Unable to start Kestrel.
System.IO.IOException: Failed to bind to address https://127.0.0.1:5001: address already in use.
 ---> Microsoft.AspNetCore.Connections.AddressInUseException: Address already in use
 ---> System.Net.Sockets.SocketException (48): Address already in use

A ps -ax | grep blazor reveals:

59023 ?? 0:05.00 dotnet /Users/adam/.nuget/packages/microsoft.aspnetcore.components.webassembly.devserver/3.2.0-preview3.20168.3/build/../tools/blazor-devserver.dll serve --applicationpath /Users/adam/Repos/blazordebug/bin/Debug/netstandard2.1/blazordebug.dll

Killing this process allows you to start a new debugging session as normal.

Further technical details

.NET Core SDK (reflecting any global.json):
 Version:   3.1.201
 Commit:    b1768b4ae7

Runtime Environment:
 OS Name:     Mac OS X
 OS Version:  10.13
 OS Platform: Darwin
 RID:         osx.10.13-x64
 Base Path:   /usr/local/share/dotnet/sdk/3.1.201/

Host (useful for support):
  Version: 3.1.3
  Commit:  4a9f85e9f8

.NET Core SDKs installed:
  3.1.200 [/usr/local/share/dotnet/sdk]
  3.1.201 [/usr/local/share/dotnet/sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.App 3.1.2 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.3 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.1.16 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.2 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.3 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]

To install additional .NET Core runtimes or SDKs:
  https://aka.ms/dotnet-download