[Snyk] Security upgrade express from 3.4.8 to 4.21.1#19

tjenkinson wants to merge 1 commit intomastertjenkinson/socket.io:masterfrom

snyk-fix-fba858582568c5f955f1a9b27172987btjenkinson/socket.io:snyk-fix-fba858582568c5f955f1a9b27172987bCopy head branch name to clipboard