Fix typos in Modules/Core
This commit fixes typos found in Modules/Core/[Test|TestingHelper]
Found via codespell -q 3 -S *.min.js -L alledges,anid,ba,childs,doubleclick,endianity,fiter,hsi,lod,nd,parms,pres,serie,sur,toi
Signed-off-by: luz paz <luzpaz@github.com>