ObjectDisposedException on .NET Core

[markvincze]

When running the metrics stream middleware, we occasionally see the following error in the logs generated by the framework:

Cannot access a disposed object.
Object name: 'WriteReqPool'.
System.ObjectDisposedException: Cannot access a disposed object.
Object name: 'WriteReqPool'.
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Infrastructure.WriteReqPool.Allocate()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.SocketOutput.WriteContext.DoWriteIfNeeded()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.SocketOutput.WriteAllPending()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.KestrelThread.DoPostWork()

Doesn't seem to cause any actual problems though.
We have to figure out if we do something incorrectly in the middleware, or this is another problem (like aspnet/KestrelHttpServer#1402 (comment)) in Kestrel itself.