Add cmd-d shortcut for (terminal) pane::SplitRight (#41139)

Add default keybinding for `pane::SplitRight` in the `Terminal` context
for all platforms.

Closes #ISSUE

Release Notes:

- Added VS Code's terminal split keybindings (`cmd` on MacOS,
`ctrl-shift-5` on Windows and Linux)

---------

Co-authored-by: dino <dinojoaocosta@gmail.com>

assets/keymaps/default-linux.json

@@ -1134,7 +1134,8 @@
       "ctrl-shift-space": "terminal::ToggleViMode",
       "ctrl-shift-r": "terminal::RerunTask",
       "ctrl-alt-r": "terminal::RerunTask",
-      "alt-t": "terminal::RerunTask"
+      "alt-t": "terminal::RerunTask",
+      "ctrl-shift-5": "pane::SplitRight"
     }
   },
   {