Use git cherry-pick instead of a patch URL as patches are not stable
(hash length changed)

Not bumping pkgrel as both newly-backported commits are for tests only.

python-tomli is not needed after https://github.com/lilydjwg/nvchecker/pull/224

* Switch to PEP 517 [2]
* Add more dependencies to make namcap happy

[1] https://github.com/lilydjwg/nvchecker/pull/220
[2] https://github.com/lilydjwg/nvchecker/pull/212

See: https://github.com/lilydjwg/nvchecker/issues/217

[1] https://github.com/lilydjwg/nvchecker/commit/ffe84cae085e61c4bda22c6f0b2c4f72d7c74ace

Somehow already-applied commits do not trigger failures for git cherry-pick :)

is missing. I asked the developer for help at
https://github.com/lilydjwg/nvchecker/commit/257b0f63fee8df04c0aed6d61d005eaa3ca46813#comments

Motivated by Python 3.10 rebuilds :)

Ref for the newly added one: https://github.com/lilydjwg/nvchecker/pull/199