Use async DNS lookup API on Windows

On Windows, the CRT teardown code interacts poorly with ASAN when
threads are blocked on system calls like `getaddrinfo`. This can cause
lingering threads to return back to a heap that's gone :) That in turn
causes an access violation that may affect the exit code of the process.
This has caused flakiness on the Win ASAN bot.

Replace the blocking `getaddrinfo` call with the asynchronous
`GetAddrInfoExW` API. This allows pending DNS lookups to be cancelled
safely in the destructor. A joinable worker thread is now used to wait
for the completion event, ensuring that threads are properly cleaned up
and do not persist after the resolver is destroyed.

Bug: none
Change-Id: I84d764428cc19392d53bc30cdb72985c1343b051
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/429183
Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#46365}