Httpx instrumentation results in a connection leak

[sam-mosleh]

Describe your environment
python 3.10.10
httpx==0.23.3
opentelemetry-instrumentation-httpx==0.36b0

Steps to reproduce

import httpx
from opentelemetry.instrumentation.httpx import HTTPXClientInstrumentor

with httpx.Client() as client:
    HTTPXClientInstrumentor.instrument_client(client)
    print(client.get("https://wtfismyip.com/json").json())

What is the expected behavior?
I expected it to run without any ResourceWarning.

What is the actual behavior?
Got ResourceWarning for each client instance