Remove jack-in dependency in favor of it being provided by the cider-nrepl dep

[bpringe]

I saw that Sean mentioned this in Slack, so I'm creating this issue to track / discuss this.

https://clojurians.slack.com/archives/CBE668G4R/p1665262266620699?thread_ts=1665257172.454249&cid=CBE668G4R