clean up cruft in SageTeX spkg

[dandrake]

As noted in #14246, the SageTeX spkg has grown a bit crufty. Some bits of the SPKG.txt refer to now vastly outdated scripts and should be fixed up.

CC: @kcrisman

Component: packages: standard

Keywords: sagetex spkg

Issue created by migration from https://trac.sagemath.org/ticket/14363

[dandrake]

comment:6

This is addressed by the new version of SageTeX. If #19072 is closed, this ticket should be closed too.

[kcrisman]

comment:7

You could just close this in any case, as duplicate of that ticket.