Add copy command action to keybinding editor context menu

[Digized]

this is a solution for #41483.

Please let me know if I need to make any changes, this being my first open source pr

[msftclas]

All CLA requirements met.

[sandy081]

@Digized Thanks for the PR.

You would need to add the actions to our keybindings registry just like other actions. Refer here

[sandy081]

@mccreeker Your request to add more copy commands is being considered and thanks to @Digized for the initiative.

The PR provides an action to copy the command in the keybindings editor. Let me know if it works for you.

Thanks.

[sandy081]

@Digized LGTM. Merged.