feat: update to node version 16

Update from node version 11.15.0 → 16.0.0.

[x] I have reviewed the code changes myself
[x] My code meets all of the acceptance criteria of the ticket it closes.
[x] I have removed unused code (e.g., console.logs, commented out blocks, etc.)
[x] I have made all necessary changes to the documentation.
[x] I have added tests to cover my changes.
[x] All new and existing tests passed.
[x] Any dependent changes have been merged and published.

EYBlockchain / timber