[Snyk] Security upgrade html-proofer from 3.14.1 to 3.15.0#22

irinazheltisheva wants to merge 1 commit intomasterhttps-githubsup-com/pixellate:masterfrom

snyk-fix-187c1364ac28c9f607b0f5f8f25d242fhttps-githubsup-com/pixellate:snyk-fix-187c1364ac28c9f607b0f5f8f25d242fCopy head branch name to clipboard