Break circular dependencies "qt/bantablemodel -> qt/clientmodel -> qt/bantablemodel"
Note that a dependency on QLocale was introduced in D8492. This PR seems to break an implicit include of QLocale, so it needs to be included explicitly.
This is a backport of Core PR18036 [1/2]
Commit https://github.com/bitcoin/bitcoin/pull/18036/commits/61eb058cc10592cfa314ba2209fb370706100e8b