doc: Add backlinks to progress reporting documentation

doc: Add backlinks to progress reporting documentation

Previously, the only place where progress reports were mentioned is in
the section for monitoring dedicated to its catalogs.  This makes the
progress reporting more discoverable, by adding links from the pages of
the commands supporting progress reports to their related catalog
views.

Author: Matthias van de Meent
Reviewed-by: Justin Pryzby, Bharath Rupireddy, Josef Šimánek, Tomas
Vondra
Discussion: https://postgr.es/m/CAEze2WiOcgdH4aQA8NtZq-4dgvnJzp8PohdeKchPkhMY-jWZXA@mail.gmail.com