Ignore all exceptions in ._sage_doc_ attribute access #19671
Description
The current docbuilder cannot cope with obj._sage_doc_ accesses raising RuntimeError for example.
Component: documentation
Author: Jeroen Demeyer
Branch/Commit: c9980ee
Reviewer: François Bissey, Karl-Dieter Crisman
Issue created by migration from https://trac.sagemath.org/ticket/19671