Update the Angular guidance page to say to use the new Angular package

[GCHQ-Developer-847]

What component is this related to?

The Angular get started instructions page.

Why do we need it?

The work to create a new Angular package (e.g. @ukic/angular) is being worked on again by an external contributor. Once this has been completed, the guidance about how to use ICDS components in an Angular app will need to be updated to reflect the fact that an Angular package is now available.

A lot of the config changes mentioned on this page likely won't be needed, as is suggested from the information in the Stencil docs.

This ticket involves determining what the new "get started" instructions need to be when the new package is available and making those changes to the page.

Related open issues

There are some Angular issues which may relate to this:
#776 (ic-ui-kit)
#850 (ic-ui-kit)
#499

[MI6-255]

Community work has been done to set this up, that can be used. Still need to consider the docs, testing, guidance and ongoing testing etc