[Redis] RedisCluster support

[sungwonh]

Redis instrumentation does not support RedisCluster (redis.asyncio.cluster.RedisCluster).

I tried to instrument RedisCluster using opentelemetry-instrumentation-redis as below, but the application did not export any traces related redis.

from opentelemetry.instrumentation.redis import RedisInstrumentor
from redis.asyncio.cluster import RedisCluster as Redis

RedisInstrumentor().instrument()

client = await Redis(host=host, port=6379)

client.get("my-key")

It would be very helpful if redis instrumentation supports RedisCluster.

[srikanthccv]

@sungwonh Would you like send a PR for this? The important part is to write wrapper functions for cluster similar to this.

[sungwonh]

@srikanthccv OK. I will send a PR for this.