docs: building suggestions update

[henryiii]

Description

Adds updated building documentation with modern suggestions for building.

These tools do require Python 3.7+. which shouldn't be too much of an issue (and we plan to drop 3.6 very soon, probably 3.7 too soon-ish).

Suggested changelog entry:

* Build docs updated to feature scikit-build-core and meson-python, and updated setuptools instructions.

[rwgk]

Nice! — Caveat: I only read through. It looks great and very helpful, but I didn't actually try out any of the suggested configs and commands (and I don't usually work directly with any of those tools).