[IMPR] Polish WikidataBot.user_edit_entity
[IMPR] Polish WikidataBot.user_edit_entity

- Fix accessing WikibasePage.
- Make the method return bool, just like BaseBot._save_page does.
- Do not automatically set current_item, this shows ugly "-1" for new
  items.

Bug: T87493
Change-Id: I91bf76085ce19bf191dcdbab73b2fb7c1b5bfac4

wikimedia/pywikibot-core,happy5214/pywikibot-core,magul/pywikibot-core,jayvdb/pywikibot-core,hasteur/g13bot_tools_new,happy5214/pywikibot-core,jayvdb/pywikibot-core,wikimedia/pywikibot-core,npdoty/pywikibot,PersianWikipedia/pywikibot-core,hasteur/g13bot_tools_new,hasteur/g13bot_tools_new,npdoty/pywikibot,Darkdadaah/pywikibot-core,magul/pywikibot-core,Darkdadaah/pywikibot-core