This is a follow-up to #29633: clean up typos and typesetting issues in various SPKG.rst files.

See also: #29655 - Improve build/pkgs/*/SPKG.rst

Depends on #29633
Depends on #29669

CC: @mkoeppe

Component: documentation

Keywords: sd109

Author: John Palmieri

Branch/Commit: c559f26

Reviewer: Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/29745