fix: update delete email notification

[tobybellwood]

Previously the delete email notification command was unusable because of a copy/pasta error from the delete webhook notifiction

tobybellwood@pop-os:~$ lagoon delete notification email -n example-email
Error: unknown shorthand flag: 'n' in -n
Usage:
  lagoon delete notification [command]

Aliases:
  notification, n

Available Commands:
  microsoftteams         Delete a Microsoft Teams notification from Lagoon
  project-email          Delete a email notification from a project
  project-microsoftteams Delete a Microsoft Teams notification from a project
  project-rocketchat     Delete a RocketChat notification from a project
  project-slack          Delete a Slack notification from a project
  project-webhook        Delete a webhook notification from a project
  rocketchat             Delete a RocketChat notification from Lagoon
  slack                  Delete a Slack notification from Lagoon
  webhook                Delete a email notification from Lagoon
  webhook                Delete a webhook notification from Lagoon

This PR fixes the email subcommand, and regens the correct docs.

[shreddedbacon]

Nice find :D