[Snyk] Upgrade mkdirp from 0.3.5 to 0.5.5#2

snyk-bot wants to merge 2 commits intomasterPhearZero-JS/grunt-source:masterfrom

snyk-upgrade-95891cff3b884568a9c0a3f9c80d2e7dPhearZero-JS/grunt-source:snyk-upgrade-95891cff3b884568a9c0a3f9c80d2e7dCopy head branch name to clipboard