[cleanup] Remove deprecated Page/Category/User methods
[cleanup] Remove deprecated Page/Category/User methods

Remove oudated Page/Category/User methods after 10 years.
The FutureWarning was made before 3.0.20200405

Change-Id: Ic8bf29636b47a0aed744301b236412d8c3f36ad2

wikimedia/pywikibot-core,wikimedia/pywikibot-core