PYTHON-4292 Improve TLS read performance

[ShaneHarvey]

PYTHON-4292 Improve TLS read performance

Use a socket timeout based approach for cancelling pending operations. This results in >=2x better throughput when reading large TLS responses from multiple threads.

Before:

time python bench-100-threads-find-large.py
Python: 3.13.0, PyMongo: 4.11.0.dev0, MongoDB: 8.0.1, auth: True, tls: True
python bench-100-threads-find-large.py  15.05s user 53.82s system 256% cpu 26.805 total

After:

time python bench-100-threads-find-large.py
Python: 3.13.0, PyMongo: 4.11.0.dev0, MongoDB: 8.0.1, auth: True, tls: True
python bench-100-threads-find-large.py  9.31s user 23.28s system 244% cpu 13.327 total

[blink1073]

LGTM!

[ShaneHarvey]

Update I also confirmed the perf improvement on a rhel8.7-small host (updated the benchmark to use 20 threads to time's sake). Before:

$ time python bench-20-threads-find-large.py
Python: 3.13.0, PyMongo: 4.11.0.dev0, MongoDB: 8.0.4-rc0, auth: True, tls: True

real	0m13.271s
user	0m12.706s
sys	0m10.766s

After:

$ time python bench-20-threads-find-large.py
Python: 3.13.0, PyMongo: 4.11.0.dev0, MongoDB: 8.0.4-rc0, auth: True, tls: True

real	0m7.784s
user	0m7.708s
sys	0m4.563s