Fix warning for intersect mode with only one gen
Fix warning for intersect mode with only one gen

The warning message was using pywikibot.input
instead of pywikibot.warning.

Change-Id: Iefc5c8b7885d73130066a6142b67e5ee7ecfa5a3

wikimedia/pywikibot-core,hasteur/g13bot_tools_new,trishnaguha/pywikibot-core,icyflame/batman,emijrp/pywikibot-core,jayvdb/pywikibot-core,xZise/pywikibot-core,npdoty/pywikibot,h4ck3rm1k3/pywikibot-core,PersianWikipedia/pywikibot-core,Darkdadaah/pywikibot-core,hasteur/g13bot_tools_new,darthbhyrava/pywikibot-local,Darkdadaah/pywikibot-core,smalyshev/pywikibot-core,VcamX/pywikibot-core,happy5214/pywikibot-core,hasteur/g13bot_tools_new,wikimedia/pywikibot-core,h4ck3rm1k3/pywikibot-core,happy5214/pywikibot-core,jayvdb/pywikibot-core,npdoty/pywikibot,valhallasw/pywikibot-core,magul/pywikibot-core,magul/pywikibot-core,TridevGuha/pywikibot-core