Shortcuts documentation: Add the PC equivalent of the Mac's "Cmd" key in the WebIDE section

This makes it consistent with the "Global" section of the file
Signed-off-by: Thomas Pathier <tpxp@live.fr>

doc/workflow/shortcuts.md

@@ -93,4 +93,4 @@ You can see GitLab's keyboard shortcuts by using 'shift + ?'
 
 | Keyboard Shortcut | Description |
 | ----------------- | ----------- |
-| <kbd>⌘</kbd> + <kbd>p</kbd> | Go to file |
+| <kbd>Cmd</kbd>/<kbd>Ctrl</kbd> + <kbd>p</kbd> | Go to file |