Add keyboard shortcut to edit snippet
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In the snippets UI (example: $1972953) there is no keyboard shortcut assigned to the <kbd>Edit</kbd> button. There is no easy way to work without a mouse to edit the snippet, you more or less have to use the mouse.
It would be nice to have the user experience aligned with Issues, Merge Requests and Wiki.
## Screenshots
### Global help
On the Snippets UI, when you press the <kbd>?</kbd> key to get help displayed on keyboard shortcuts, you find out there is no shortcut to quickly start editing.

Currently supported and mentioned on the "Keyboard shortcuts" help dialog are: Wiki, Epics, Issues and Merge Requests.
### Edit buttons
Here is the tooltip of the <kbd>Edit</kbd> button on an Issue and a Merge Request, for example. It should be similar on a Snippet.


issue