Add an additional keyword arg to RedisInstrumentor.intrument to ignore root spans 🌈 🙏

Hello everyone, I'm new to the OTEL community (and python 🌈 ( and writing github issues)).

I've been trying to instrument a python app with the RedisInstrumentor.

I have an issue with noisy redis spans in my collector. Ideally, I don't want to collect any spans without a parent_id attached.

It would be neat to be able to pass an additional keyword arg (something along the lines of trace_root_span) so that when the instrument method is called, it breaks out early and does not process any span where span.parent is None.

eg: RedisInstrumentor().instrument(request_hook=request_hook, response_hook=response_hook, trace_root_span: false)

I saw this neat configuration option in the ruby redis instrumentation which ignores spans without a parent id.

I thought I would be able to use the response_hook to ignore spans without a parent but I still saw spans in my collector as the response is returned here.

Additional context
I may be missing something obvious and happy to close the issue (or try open a PR) if there is a way to do this via a response_hook 👍

Start in instrumentation/opentelemetry-instrumentation-redis/src/opentelemetry/instrumentation/redis/init.py around the span handling near line 159, and inspect how RedisInstrumentor.instrument processes its keyword arguments. Confirm the desired behavior for spans whose parent is None, then add coverage showing that the option suppresses root spans while retaining child spans.