Session resumption is not a reliable TLS behavior: the server can decide
to reject a session ticket for a number of reasons, or no reason at all.
This makes this non-hermetic test extremely brittle.
It's currently broken on the builders for both TLS 1.2 and TLS 1.3, and
I could reproduce the issue for TLS 1.3 only. As I was debugging it, it
started passing entirely on my machine.
In practice, it doesn't get us any coverage as resumption is already
tested with the recorded exchange tests, and TestVerifyHostname still
provides a smoke test checking that we can in fact talk TLS.