Upgrade to node 16

[ikstewa]

GitHub Actions are requesting a migration of all actions from node12 to node16. https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/

As a result we're receiving warnings in our workflows from this action:

Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: zaproxy/action-baseline