Refactor XDS UDP Listener for UDPRoute

[arkodg]

Description:

Describe the issue.

Similar to https://github.com/envoyproxy/gateway/issues/1635, we need to make sure the XDS Listener name is based off the UDP Listener name to make sure the XDS listener does not flap when UDPRoutes churn.

Requires work similar to https://github.com/envoyproxy/gateway/pull/3271

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Any extra documentation required to understand the issue.

[arkodg]

hey @aoledk interested in this one ?

[aoledk]

/assign