Fix ConfluentKafkaInstrumentor usage

[jltvieira]

Describe your environment
Docker image running python:3.10.7-slim-bullseye as base

Steps to reproduce

from opentelemetry.instrumentation.confluentkafka import ConfluentKafkaInstrumentor

# Instrument kafka
ConfluentKafkaInstrumentor().instrument()

What is the expected behavior?
Instrumentation to work just by adding the lines above.

What is the actual behavior?

ModuleNotFoundError: No module named 'opentelemetry.instrumentation.confluentkafka'

Additional context
The solution is to actually make the import like this:

from opentelemetry.instrumentation.confluent_kafka import ConfluentKafkaInstrumentor

[srikanthccv]

This isn't really a bug with the package. The docs have a typo. Feel free to send pull request.