helpers: Fix minor typo in content_test.go
helpers: Fix minor typo in content_test.go

mdhender/hugo,MarkDBlackwell/hugo,vbatoufflet/hugo,fedelibre/hugo,tubo028/hugo,abourget/hugo,bogem/hugo,tubo028/hugo,fedelibre/hugo,tischda/hugo,fedelibre/hugo,jygastaud/hugo,tischda/hugo,bogem/hugo,mdhender/hugo,Zenithar/hugo,ffrizzo/hugo,ffrizzo/hugo,gohugoio/hugo,MarkDBlackwell/hugo,mitchchn/hugo,vbatoufflet/hugo,anthonyfok/hugo,gohugoio/hugo,jygastaud/hugo,digitalcraftsman/hugo,mayah/hugo,melo/hugo,Zenithar/hugo,melo/hugo,mdhender/hugo,anthonyfok/hugo,gohugoio/hugo,mayah/hugo,soundrussian/hugo,soundrussian/hugo,digitalcraftsman/hugo,anthonyfok/hugo,fedelibre/hugo,abourget/hugo,mdhender/hugo,mitchchn/hugo