Update `installation-steps.md`

[bryophyta]

There are a few points which out of date in the installation guide in our docs:

• [ ] The TOC is not up to date (e.g. it's missing a heading for 'Basic Tools')
• [ ] The guidance on 'basic tools' is quite vague about what's needed, and I believe that Homebrew is now installed as part of the standard onboarding setup guide.
• [ ] The command for installing Homebrew is out of date; should be updated or removed, depending on the previous point.
• [ ] The recommended way to find the most recent Java 11 package in SDKMan doesn't match any of the packages currently available (checked on 2022/11/07)
• [ ] We should probably review the node.js recommendations.

All of these issues seem like they could be solved in a couple of different ways, and I'm not confident that I know what the best recommendations are. But I'm opening this issue as a way to keep track of them for future review.