Add IPv4 / IPv6 force flags

[peanball]

Please provide details on the following items. Failure to do so may result in deletion of your feature request.

What's the user value of this feature request?

The CF API, like any HTTP endpoint, can be exposed via IPv4, IPv6 or both. Popular network tools such as nslookup, curl, dig, etc. provide the option to force one or the other version in scenarios where e.g. both are available.

Who is the functionality for?
People that interact with CloudFoundry through limited networks, e.g. those that only support IPv4 reliably but also claim IPv6 support.

How often will this functionality be used by the user?
Probably not very frequently, but when you need it, it will be very useful.

Who else is affected by the change?
Not a breaking change, just more control for operators.

Is your feature request related to a problem? Please describe.
Like with cURL, this flag is intended to force a particular IP protocol version, which can be used for troubleshooting and debugging inherent network issues in communicating with the CC API.

Describe the solution you'd like
A flag that allows forcing -4 for IPv4 and -6 for IPv6 resolution of the CF API endpoint, and subsequent calls (e.g. links retrieved from the API endpoint that are then followed)

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context

Note:
As of the GA of the v7 CLI, the v6 line is no longer under active development and will be updated only to patch CVEs or fix severe blocking defects with no workarounds.