Make UserContributionsGenerator use the provided site object
Make UserContributionsGenerator use the provided site object

Change-Id: I825b5c7d7909963c0bd0844fa9e7291ac51ec58b

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