Update setup steps on settings page

[Jeffrey Paul]

Is your enhancement related to a problem? Please describe.
Our setup steps evolved a bit since finalizing our settings page, so we should look to get those steps updated to match what's described in our readme.

Describe the solution you'd like

• update text/links on settings page to match the configuration steps in the readme

Designs
n/a

Describe alternatives you've considered
n/a

Additional context
Will want to ensure this inherits changes from #57.

[Jeffrey Paul]

Note that if we take action on #64 that this issue (#61) is no longer needed though we may want to similarly port the config steps from the readme into the in-Gutenberg block-based settings config.