Ubuntu-24 no longer includes the Heroku CLI as part of the runner image

[qbunt]

Either the documentation in this repo needs updating for the version released 2 days ago, or the install should be packed into this action. Full list of packages here

[AkhileshNS]

Thanks for raising, I've updated the documentation.

[qbunt]

@AkhileshNS Thanks for the fast response, was super surprising to see they had dropped so much out of the runner images for 24