Tests: Correct @var annotation in REST users controller tests.
The $query variable comes from the pre_user_query filter args and is a WP_User_Query instance, the assertInstanceOf( WP_User_Query::class, ... ) on the line above asserts exactly that. The docblock incorrectly declared it as WP_User.
Developed in https://github.com/WordPress/wordpress-develop/pull/12834.
Follow-up to r59899.
Props Soean.
See #64894.