Simplification of setting mocks for Selectors and Domains

[foxysolutions]

2023-06-05: fflib_Application.cls: Extending Selector and Domain Factories with setMock() method which doesn't require .sObjectType() to be mocked

• Feature to allow simplifying how a Selector and/or Domain are being stubbed
• To prevent forgetting to mocks.when() the method .sObjectType(), causing unexpected and undesired test method results (especially for juniors)
• Additionally, this aligns nicely with setMock() for Services where the Interface method is provided
• New approach is 100% backward compatible with a little hint for developers as reminder to mock the sObjectType()-method
• Original code to mock a Domain class:

  mocks.startStubbing();
  mocks.when( m_domLeads.sObjectType() ).thenReturn( Lead.SObjectType );
  mocks.stopStubbing();
  Application.domain.setMock( m_domLeads );

• New code: Application.domain.setMock( Lead.SObjectType, m_domLeads );

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This change is 

[foxysolutions]

@ImJohnMDaniel I've updated the branch to match master again, but not sure if that was the only reason why you assigned it back to me? Thanks!

[ImJohnMDaniel]

@foxysolutions -- you are all good. I routinely "assign" PRs to the person that opened it. Just waiting for reviews from other team members (who may actually be on PTO this week), so I ask for your patience.

[foxysolutions]

@afawcett @ImJohnMDaniel any review possible on this small change, to simplify how mocks are being set? It was already reviewed once, so pending for 2nd one. Cheers!

[wimvelzeboer]

@foxysolutions If you already want to start working with this new method, then you can also add the fflib-apex-extensions repo to your project. The fflib_ClassicXXXFactory and the fflib_DynamicXXXFactory already have this method.