add bytes limit feature to batch processor

[yutingcaicyt]

Is your feature request related to a problem? Please describe.
When I use Otel, I find it very difficult to limit the bytes size of a request to the destination. The 'sendBatchMaxSize' in batch processor only limits the number of logs, not the bytes size. If the size of a request cannot be accurately limited, it will cause some trouble to the receiving end.

Describe the solution you'd like
Maybe we can add a feature that limits the bytes size of a batch into the batch processor.

[seankhliao]

The byte size depends a lot on the final exporter protocol / encoding.
It doesn't seem like the batch processor will have sufficient information to calculate this accurately?

[yutingcaicyt]

It does make sense. So is the best way to handle this in the final exporter? However, This doesn't feel very generic.

[dmitryax]

This is something we can have once #8122 is implemented

[nicolastakashi]

This is something we can have once #8122 is implemented

@dmitryax is this still a requirement?