[1.6.x] Fixed typo in docs/ref/request-response.txt.

Backport of 49d034fff21213b369c08b39772e0437c3cc723b from master
[1.6.x] Documented a current limitation of multiple table annotation; refs #10060.

Backport of 4b23a6c7a9232cc07ec95fe98be17efbd4449822 from master
[1.6.x] Fixed typo in aggregation docs.