[FIX] TokenWallet: Assert a username
[FIX] TokenWallet: Assert a username

Follow up to Iccce554b5c9e83a42ae87c0bd69e38f880e3f6ac

Fixes another place where assert would fail if the
sysop username is different to the normal username.

Bug: T74238
Change-Id: I7c438e16d40ff7128980fd2eecf1575eeac40114

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