Pre-launch updates - Githubissues

Steven and I have made some amends to the page template for the GitHub.io page that was called "HMRC Design System". These comprise:

Changing the name from "HMRC Design System" to "HMRC Assets Frontend components and patterns" to ensure there is one source of truth
Amending the section previously called "Help and Support" to reduce confusion around where and what people should be contributing to
Updating out of date links

hmrc / component-library-template