MiniBlog does not work with .NET 6

[jiangzeng01]

Application Name: MiniBlog
OS: Windows 10 RS5
CPU: X64
.NET Build Number: 6.0.100-alpha.1.21064.27
App Source on GitHub link: https://github.com/madskristensen/MiniBlog

Verify Scenarios:
1). Windows 10 RS5 X64 + .NET Core SDK build 6.0.100-alpha.1.21064.27: Fail
2). Windows 10 RS5 X64 + .NET Core SDK build 5.0.101 : Pass
3). Windows 10 RS5 X64 + .NET Core SDK build 3.1.300 Pass

Repo Machine Environment Info:
C:\h\w\AA5A0904\p>dotnet --info
.NET SDK (reflecting any global.json):
Version: 6.0.100-alpha.1.21064.27
Commit: 4239e5cd10

Runtime Environment:
OS Name: Windows
OS Version: 10.0.17763
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\6.0.100-alpha.1.21064.27\

Host (useful for support):
Version: 6.0.0-alpha.1.21063.13
Commit: 6ded57b3d2

.NET SDKs installed:
6.0.100-alpha.1.21064.27 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 6.0.0-alpha.1.21063.28 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.0-alpha.1.21063.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.0-alpha.1.21062.4

Repro steps:
On Cmd, start the app by running : dotnet Miniblog.Core.dll
Go to http://localhost:5000/
Expected Result:
App should run

Actual Result:
Page isn't working

Findings:
IHttpBufferingFeature removed in .net6, it breaks the app.
fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[1]
An unhandled exception has occurred while executing the request.
System.TypeLoadException: Could not load type 'Microsoft.AspNetCore.Http.Features.IHttpBufferingFeature' from assembly 'Microsoft.AspNetCore.Http.Features, Version=6.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'.
at WebMarkupMin.AspNetCore2.WebMarkupMinMiddleware.ProcessAsync(HttpContext context, Boolean useMinification, Boolean useCompression)
at System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[TStateMachine](TStateMachine& stateMachine)
at WebMarkupMin.AspNetCore2.WebMarkupMinMiddleware.ProcessAsync(HttpContext context, Boolean useMinification, Boolean useCompression)
at WebMarkupMin.AspNetCore2.WebMarkupMinMiddlewareBase.Invoke(HttpContext context)
at WebEssentials.AspNetCore.OutputCaching.OutputCacheMiddleware.ServeFromMvcAndCacheAsync(HttpContext context)
at WebEssentials.AspNetCore.OutputCaching.OutputCacheMiddleware.InvokeAsync(HttpContext context)
at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
at WilderMinds.MetaWeblog.MetaWeblogMiddleware.Invoke(HttpContext context, MetaWeblogService service)
at Microsoft.AspNetCore.Diagnostics.StatusCodePagesMiddleware.Invoke(HttpContext context)
at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.g__Awaited|6_0(ExceptionHandlerMiddleware middleware, HttpContext context, Task task)

[jiangzeng01]

Ref: dotnet/aspnetcore#29341