[IMPROV] Test static generator directly
[IMPROV] Test static generator directly

With the introduction of the static method Request._build_mime_request
in c7a8dc0199829a303d70a2973ac2eeddacc8ddcc it is possible to test it
directly and not do the same transformations again which could introduce
copy and paste errors.

Change-Id: Id40ab25cdcb31d19ed2d859374a969a33d81c87b

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