Fix benchmark so the buffer is read each time.
Fix benchmark so the buffer is read each time.

The bytes.Buffer was exhausted after the first read.  Creating a new
reader each invocation catpures the correctly timing.

kujohn/hugo,jygastaud/hugo,fhergomez/hugo,halostatue/hugo,badoet/hugo,fedelibre/hugo,jygastaud/hugo,melo/hugo,bramp/hugo,soundrussian/hugo,gohugoio/hugo,digitalcraftsman/hugo,derekperkins/hugo,mayah/hugo,anthonyfok/hugo,MarkDBlackwell/hugo,derekperkins/hugo,sprig/hugo,ifraixedes/hugo,anthonyfok/hugo,bogem/hugo,vbatoufflet/hugo,tjyang/hugo,gohugoio/hugo,mdhender/hugo,ryanclarke/hugo,anthonyfok/hugo,mdhender/hugo,halostatue/hugo,tubo028/hugo,badoet/hugo,kujohn/hugo,abourget/hugo,tatsushid/hugo,tatsushid/hugo,mdhender/hugo,fhergomez/hugo,digitalcraftsman/hugo,mayah/hugo,mitchchn/hugo,sprig/hugo,bogem/hugo,mdhender/hugo,fedelibre/hugo,coderzh/hugo,coderzh/hugo,gohugoio/hugo,ryanclarke/hugo,bramp/hugo,mitchchn/hugo,soundrussian/hugo,MarkDBlackwell/hugo,tischda/hugo,tubo028/hugo,abourget/hugo,tjyang/hugo,ifraixedes/hugo,fedelibre/hugo,Zenithar/hugo,ffrizzo/hugo,ffrizzo/hugo,melo/hugo,Zenithar/hugo,vbatoufflet/hugo,fedelibre/hugo,tischda/hugo