Update feature status page for ambient beta for 1.22

[linsun]

[ericvn]

Note that this requires changes in https://github.com/istio/enhancements, namely a new document in features and a corresponding update in features.yaml. This will need to be cherry-picked to the release-1.22 branch so that it shows up in the docs.

[abhayporwals]

Hey! So, Can I make changes in the istio/enhancements repo?

[craigbox]

done, pinged https://github.com/istio/istio/pull/52524 to get any updates for 1.23, which should only have been dual stack.