[package_info_plus] Support `win32: 6.0.0`

[Zazo032]

What is your question?

We can't update win32 dependency to the latest version because wakelock_plus has a pinned dependency. There are some breaking changes, not sure how much could they affect this plugin.
Because wakelock_plus 1.4.0 depends on win32 ^5.6.1 and no versions of wakelock_plus match >1.4.0 <2.0.0, wakelock_plus ^1.4.0 requires win32 ^5.6.1.
So, because sample_app depends on both wakelock_plus ^1.4.0 and win32 ^6.0.0, version solving failed.

wakelock_plus can't be updated to win32: 6.0.0 because package_info_plus doesn't support it.

fluttercommunity/wakelock_plus#120 (comment)