Please allow both `gh stack` and `gh stacks` commands to work

[matthewhively]

I find myself continually accidentally typing gh stacks which is un-recognized.
Yeah, I know its my dumb fault, but it seems simple enough to add an alias for stacks => stack in the plugin's CLI.
Please consider it.

[81reap]

You could use aliases as a workaround https://www.w3schools.com/bash/bash_alias.php