Improve the Kafka brokers Grafana dashboard

[scholzj]

The "Log size" chart in our Kafka brokersGrafana dashboard is not that great. It shows each partition replica, so even in a very small cluster, you can very easily have few hundred items in it (just the default __consumer_offsets partition replicas make 150 items). This can be surely improved. SOme of the ideas were:

• Replacing it with table with paging?
• Using panels to be able to colapse it instead of rendering it all the time
• Spliting th dashboard into separate parts

This is one of the issues based on feedback from the Strimzi Survey 2022

[tombentley]

Triaged on community call 1/12/2022. This seems like a good improvement that we should try to implement.

[maciej-tatarski]

I can work on it if help is still needed. This is how it would looks like with pagination and table (sorted by log size):

[maciej-tatarski]

@scholzj let me know if this is still needed

[scholzj]

@maciej-tatarski I think this would be useful. Are you able to make it work across the different Grafana versions? Thanks.

[maciej-tatarski]

I tested it with grafana 7.3.7, 7.5.7:

and 10.3.4:

[scholzj]

Yeah, that looks good I think.

[maciej-tatarski]

Sure, I'll make a PR soon