Add open vim keymap command (#9953)

Release Notes:

- Added a `vim: open default keymap` command to show the default Vim
keymap ([#8593](https://github.com/zed-industries/zed/issues/8593)).

Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>
339b29ef17Mehmet Efe Akça committed on 4/10/2024, 11:03:13 PM· committed by GitHubparentd1ad967
3 files changedLine totals unavailable