Misc/NEWS.d/next/Library/2021-10-08-04-11-55.bpo-10716.QSRVK2.rst

Migrated pydoc to HTML5 (without changing the look of it). Side effect is to
update xmlrpc's ``ServerHTMLDoc`` which now uses the CSS too. cgitb now
relies less on pydoc (as it can't use the CSS file).