[FEATURE] Support pickle serializer

[dogrocker]

Thank you for create celery insights.

It would be great if there was a pickle serializer.

[danyi1212]

Hey, thanks for the suggestion! 🌟
To be honest, I've never worked with the pickle serializer in Celery.

Since Celery Insights uses Celery directly, it mostly gives Celery the sole responsibility of serializing the events and results.
There might need to be some tweaks and optimizations for working with the Pickle serializer.

Have you tried to implement it yourself?
Feel free to share any exceptions raised in the Celery Insights server when using Pickle and I'll happily help you with developing it 🙂