Support keystrokes for test formatting in Editor Lite

!37151 (merged) introduced the keystrokes formatting for markdown text in simple editing fields like comment, description, etc. This issue is supposed to introduce the same keystroke-formatting for Editor Lite to provide consistent editing experience for the users.

The following discussion from !41010 (merged) should be addressed:

• @dmishunov started a discussion: (+3 comments)

  Thanks for the clarification @digitalmoksha. Now, that I checked the code and clicked around, I see one issue.

  First of all, as far as I understand the concern of this MR is exactly to make the button on the toolbar to generate the italicized text using _…_. And this part works great in all editors where the markdown toolbar is used.

  However, now, getting back to the original MR !37151 (merged) where you introduced the keystroke for wrapping the text, we get the differences in the behavior that, I suppose, will confuse users a lot: they will be able to use the keystrokes in comments, descriptions, etc. but not in the editor. This is especially confusing when working with Snippets, where we don't have the markdown toolbar even when working with the markdown blobs (apparently deserves the separate issue to add it, actually).

  @digitalmoksha I am going to create. follow-up issue to tackle this problem to have something that we (probably in Create::Editor) could schedule and implement using !37151 (merged) as an example.

  You don't need to do anything about it as this is additional functionality that is irrelevant to the scope of this MR.