feat: Add Tutorial For BGP with NCC and Star

[joshw123]

Description

Adding NCC and BGP Option; which avoids the use of the Internal LoadBalancer with Start Topology.

Motivation and Context

Allows Dynamic Routing Exchange between Palo Alto and NCC Cloud Routers as an alternative to Internal LoadBalancer;

How Has This Been Tested?

Terraform has fully rolled out to my own project and fully tested connectivity as per the README etc.

Screenshots (if appropriate)

Types of changes

• New feature (non-breaking change which adds functionality)

Checklist

• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes if appropriate.
• All new and existing tests passed.

[joshw123]

Hey @mattmclimans Would it be possible to get this reviewed? :)

Thank You!