Fixed typo in description of categories and tags (#6896)
Fixed typo in description of categories and tags (#6896)

Merge pull request 6896
fulldecent/jekyll,jekyll/jekyll,fulldecent/jekyll,tillgrallert/jekyll,jaybe-jekyll/jekyll,Strangehill/jekyll,Strangehill/jekyll,chrisfinazzo/jekyll,jaybe-jekyll/jekyll,jaybe-jekyll/jekyll,yhironaka/yhironaka.github.io,getandpost/jekyll.github.io,tillgrallert/jekyll,x-way/jekyll,jekyll/jekyll,ryanshaw/jekyll,x-way/jekyll,ryanshaw/jekyll,tillgrallert/jekyll,Strangehill/jekyll,Strangehill/jekyll,chrisfinazzo/jekyll,ryanshaw/jekyll,getandpost/jekyll.github.io,jekyll/jekyll,fulldecent/jekyll,getandpost/jekyll.github.io,jaybe-jekyll/jekyll,chrisfinazzo/jekyll,tillgrallert/jekyll,x-way/jekyll,chrisfinazzo/jekyll,x-way/jekyll,fulldecent/jekyll,jekyll/jekyll,tillgrallert/jekyll,ryanshaw/jekyll,Strangehill/jekyll