Optimize get_live_deployments

[jugalshah291]

Why are these changes needed?

The _get_live_deployments function internally calls get_deployments_in_application that iterates over self._deployment_state ( that stores all the live deployments) and filters out deployment for a specific app. This is inefficient especially when you have a large of serve application running. (For every serve application we are iterating over all the deployments)

Related issue number

Closes #45793

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[zcin]

LGTM, thanks!

[abrarsheikh]

nice :)