Latest release notifier while invoking NF

[abhi18av]

Proposal

With the latest releases for NF (and the sibling products Tower), generally speaking, using the latest versions of NF would be ideal. As a user, it'd be nice to know when there's a new edge/stable release of NF.

Ideally, whenever people launch a workflow using NF - the logs can print something like There’s a new edge/stable release xxxxx.

We can take some inspiration from the gh CLI tool

> gh
...
...

A new release of gh is available: 1.8.1 → v1.9.2
To upgrade, run: brew update && brew upgrade gh
https://github.com/cli/cli/releases/tag/v1.9.2