WP-CLI: Add "wp cavalcade job delete"

[r-a-y]

On our install, sometimes we see the same job for the same hook being duplicated multiple times with the same nextrun timestamp.

Regardless of my example, instead of using a SQL query to delete a job or multiple jobs, it would be handy if there was a wp-cli command that allowed us to remove said jobs.

If this sounds like a good idea, I recommend wp cavalcade job delete for this new subcommand, but that means a wp cavalcade job command should be created as this currently doesn't exist.

What do you think?