Finishing TODO in pingora-core rustls listeners to avoid panicking

https://github.com/cloudflare/pingora/blob/e6e677fe9b58555140ab7bd14feff035392b3530/pingora-core/src/listeners/tls/rustls/mod.rs#L49-L60

Wrapping this in a Result might solve this? PR incoming soon.

Start with pingora-core/src/listeners/tls/rustls/mod.rs at lines 49-60 and inspect the TODO and its surrounding rustls listener entry point. Determine how the acceptor failure is currently handled and whether the proposed Result direction fits the existing API. Done means the TODO is resolved and this path no longer panics on the relevant failure.

Written by the indexing model from the issue text.