Switch to simpler review app styling etc

[colinrotherham]

Description

This PR includes:

1. Switch to simpler review app styling
2. Removes "Install" and "About" guidance pages
3. Deploys to GitHub pages automatically when merging into main

Point 3) means we can preview the latest nhsuk-frontend app between releases

Checklist

• Tested against our testing policy (Resolution, Browser & Accessibility)
• Follows our coding standards and style guide
• CHANGELOG entry

[anandamaryon1]

I use the currently deployed frontend Github pages site as a reference often, perhaps it's only useful for me though?

But, I'd love to have a test/review/dev app for frontend, but probably not pointing to main, maybe a staging/review branch instead?

Perhaps we could have both? Or all three, with this proposal sitting in between? So a Prod, Review and Dev environment?

[colinrotherham]

I use the currently deployed frontend Github pages site as a reference often, perhaps it's only useful for me though?

@anandamaryon1 To help support #1099 what do you think of simpler review app styling?

I've pushed it up, similar to https://govuk-frontend-review.herokuapp.com now

[anandamaryon1]

Nice, a useful stepping stone to having a more useful review app for testing new work. And having the hero notice to alert users to what this is helpful too.

@colinrotherham If merged will this replace this PR: #1201? Or should we merge that one and adjust this one to be compatible ahead of merging it too?

[colinrotherham]

@colinrotherham If merged will this replace this PR: #1201? Or should we merge that one and adjust this one to be compatible ahead of merging it too?

@anandamaryon1 I'd like to merge #1201 first and update this PR