Remove or update included about_ help files

[fflaten]

Checklist

• Issue has a meaningful title
• I have searched the existing issues. See open documentation issues

Where did you see it?

Pester (latest)

Function name

about_*

What is the issue?

Pester includes offline help in about_* format which has not been updated for Pester v5. Before releasing v6 there's a choice to be made:

• Update?
• Remove and solely depend on https://pester.dev and command help? Maybe keep about_Pester as a simple introduction and reference to the website?

Related files found here https://github.com/pester/Pester/tree/main/src/en-US:
about_BeforeEach_AfterEach
about_Mocking
about_Pester
about_Should
about_TestDrive

[nohwnd]

delete? no-one is using those apparently. Or I don't recall a single issue that says the files are updated.

[fflaten]

I agree. Keep a simple intro and links in about_Pester?

See related comment pester/docs#280 (comment)