Upgrades to jsonwebtoken v9, fixing a number of vulnerabilities. Please see the jsonwebtoken v8-v9 notes: https://github.com/auth0/node-jsonwebtoken/wiki/Migration-Notes:-v8-to-v9
馃毃 Note jsonwebtoken has dropped support for Node < 12 (Node v10 went end of life 2021-04-30, Node v11 EOL was 2019-06-01); in order to get these security fixes we had no choice but to also drop support for Node versions prior to v12.