Make Ctrl+R in Vi EditMode same as Windows

[davetapley]

PR Summary

Fix #2453

Make ctrl+r in Vi EditMode same as Windows (#2453)

Existing functionality (ViSearchHistoryBackward, SearchForward) already available via / and ? shortcuts.
But ReverseSearchHistory and ForwardSearchHistory had no shortcuts.

Also copy ctrl+s and ctrl+g since these have no conflicts in vi mode.

Remove vi mode existing tests and copy (almost) verbatim from InteractiveHistorySearch to VIInteractiveHistorySearch.

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Make sure you've added one or more new tests
• Make sure you've tested these changes in terminals that PowerShell is commonly used in (i.e. conhost.exe, Windows Terminal, Visual Studio Code Integrated Terminal, etc.)
• User-facing changes
  • Not Applicable
  • OR
  • Documentation needed at PowerShell-Docs
    • Doc Issue filed: Remap Ctrl+R to ReverseSearchHistory in EditMode vi MicrosoftDocs/PowerShell-Docs#7600

Microsoft Reviewers: Open in CodeFlow

[daxian-dbw]

@davetapley I made some updates to the tests, but when pushing my changes to your branch, I accidentally pushed my master branch to your fork, because you were using the master branch for this PR. That caused this PR to be closed.
I opened #3148 instead, with your original first commit, and will have that one merged.