Add nodejs LTS `iron` Docker image

This version provides the current awsudo release with

• updated dependencies and
• an additional Docker image for the new LTS, code-named Iron

⚠️ Notice ⚠️

This is the last version that will support, or include Docker images for, node 16 (fermium) or 18 (gallium).
They are no longer under maintenance, and will be removed in line with documented project policy.

What's Changed

• Add nodejs LTS iron Docker image by @jtheriault in #75

Full Changelog: v2.0.0...v2.0.1