[chore] [processor/batch] docs: stop recommending Batch processor (#13191)

Removes the sentence in Batch processor docs recommending using the
component on every collector.

This implements one of the points proposed in:

- #12443

> - Stop recommending to configure the Batch processor on every
collector pipeline.

Author: andrzej-stencel

processor/batchprocessor/README.md

@@ -18,7 +18,6 @@ batches. Batching helps better compress the data and reduce the number of
 outgoing connections required to transmit the data. This processor supports
 both size and time based batching.
 
-It is highly recommended to configure the batch processor on every collector.
 The batch processor should be defined in the pipeline after the `memory_limiter`
 as well as any sampling processors. This is because batching should happen after
 any data drops such as sampling.