docs: Add Firebase Hosting to usage.md
docs: Add Firebase Hosting to usage.md

fedelibre/hugo,anthonyfok/hugo,mayah/hugo,gohugoio/hugo,bogem/hugo,bogem/hugo,jygastaud/hugo,mdhender/hugo,digitalcraftsman/hugo,mitchchn/hugo,fedelibre/hugo,fedelibre/hugo,mayah/hugo,mdhender/hugo,mitchchn/hugo,mdhender/hugo,Zenithar/hugo,Zenithar/hugo,anthonyfok/hugo,anthonyfok/hugo,digitalcraftsman/hugo,gohugoio/hugo,MarkDBlackwell/hugo,gohugoio/hugo,MarkDBlackwell/hugo,tubo028/hugo,tubo028/hugo,mdhender/hugo,fedelibre/hugo,jygastaud/hugo