gh-36774: `build/pkgs/nauty`: Update to 2.8.8; use VERSION in all `upstream_url`s.
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https://pallini.di.uniroma1.it/changes24-28.txt
Also, motivated by a mistake I made while preparing this PR
(https://github.com/sagemath/sage/pull/36774#issuecomment-1826867926),
and previously in #35380 (see #36781), and countless other times, I am
changing all `upstream_url`s to use `VERSION` instead of the hardcoded
version number. This makes it less error-prone to use `sage -package
update SPKG NEW_VERSION` and `sage -package update-latest`. These
commands now also display the URL from which they are downloading the
tarball, and they warn if the `upstream_url` field does not contain the
`VERSION` variable.
(Exceptions: `ipykernel`, which is fixed in #36129, and `libbraiding`,
which is fixed in #36781)
Because some of the `upstream_url` need the version in a different
format, a mechanism to refer to the components of a version is added:
The strings `VERSION_MAJOR`, `VERSION_MINOR`, `VERSION_MICRO` can be
used. For added readability, instead of the naked strings, also the
notation `${VERSION_MAJOR}` etc. can be used. For example, `nauty`,
which previously had to use a hardcoded version number, now uses the
upstream URL pattern
`upstream_url=https://pallini.di.uniroma1.it/nauty${VERSION_MAJOR}_${VER
SION_MINOR}_${VERSION_MICRO}.tar.gz`
The syntax `${VERSION_MAJOR}`, borrowed from Bourne shell, matches what
sage-bootstrap already uses in
https://github.com/sagemath/sage/blob/develop/.upstream.d/10-SAGE_SERVER
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### :hourglass: Dependencies
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- Depends on #36771 (merged here)
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URL: https://github.com/sagemath/sage/pull/36774
Reported by: Matthias Köppe
Reviewer(s): David Coudert
