Implement the TM provider of Local-TM

[JadynWong]

• EFCore DbProvider
• Mongo DbProvider
• UTs
• Docs

[gdlcf88]

@JadynWong - What do you think about these:

1. Create a Stepping.TmProvider.LocalTm.HostedServiceProcessor project. Move the HostedService and the distributed lock to it.
2. Rename the project Stepping.TmProvider.LocalTm to Stepping.TmProvider.LocalTm.Core.
3. Create a new Stepping.TmProvider.LocalTm project that depends on Stepping.TmProvider.LocalTm.Core and Stepping.TmProvider.LocalTm.HostedServiceProcessor.

That means if someone doesn't want to use the hosted service but (maybe) Hangfire or else, he doesn't need to care about the implementation of ISteppingDistributedLock and installs only the Stepping.TmProvider.LocalTm.Core package.

[gdlcf88]

I created a test app project for local TM. It seems that submitting without invoking the prepare API cause error. Please support this case.

[JadynWong]

I created a test app project for local TM. It seems that submitting without invoking the prepare API cause error. Please support this case.

Resolved.

[gdlcf88]

@JadynWong - I made this change and expected Step2 could retry after 2s, but it takes about 1min:

Stepping.NET/test/Stepping.TmProviders.LocalTm.TestApp/Program.cs

Lines 60 to 66 in de60baf

	if (!canExecuteStep2)
	{
	canExecuteStep2 = true;
	Console.WriteLine("Step 2 deliberately failed to execute and waited for the TM to pick it up.");
	context.Response.StatusCode = 500;
	return Task.CompletedTask;
	}

[gdlcf88]

@JadynWong - Great implementation! It's all LGTM.

I added a new to-do "Docs" in the top comment. I believe we can merge this PR when it is completed.