Add `feast plan`

Is your feature request related to a problem? Please describe. When we wanted to move from prototyping to production, we had to execute multiple times feast apply locally and in our CI/CD environment. We ended up deleting everything when we were just trying things differently. It would have been nice to just pass an option like --dry-run to print but not execute what feast apply wants to do

Describe the solution you’d like A clear and concise description of what you want to happen. A very common option would be to add the option --dry-run to feast apply. Another possible one is to create another command (eg: feast plan)

Describe alternatives you’ve considered A clear and concise description of any alternative solutions or features you’ve considered.

Additional context Add any other context or screenshots about the feature request here.

[woop]

Good article over here: https://www.gresearch.co.uk/article/in-praise-of-dry-run/

Adding this to our backlog for development. Won’t land soon, but it’s important to have.

[adchia]

Note that we have minimally launched some of this (diffing of Feast FCOs like FeatureViews) in Feast 0.17, which the upcoming release to include details on the infrastructure diffs as well.