tox.ini: Add opensuse, add/update opensuse.txt across build/pkgs/

[jengelh]

To test openSUSE Leap:

tox -e docker-opensuse-standard

Depends on #30663
Depends on #30900
Depends on #30899

CC: @kliem @dimpase @jhpalmieri @seblabbe

Component: packages: standard

Author: Jan Engelhardt, Matthias Koeppe

Branch/Commit: e5d114b

Reviewer: Matthias Koeppe, Jonathan Kliem, Dima Pasechnik

Issue created by migration from https://trac.sagemath.org/ticket/30619

[jengelh]

comment:1

(singleton repository with write permissions for everyone‽ No bot seems to add a note to the ticket when a push occurs. Very strange, this Trac system.)

    e4a917d10ec495da90818eeaa60b7711c2e3cf25        refs/heads/u/gh-jengelh/30619

A number of third-party packages are available, or will be Real-Soon-Now™, in openSUSE. Add their package names or virtual names according to the txt file scheme of the other distros.

[fchapoton]

New commits:

e4a917d

build/pkgs/*: add/update distros/opensuse.txt

[fchapoton]

Commit: e4a917d

[fchapoton]

Branch: u/gh-jengelh/30619

[fchapoton]

comment:3

you need to write your real name in the Author field above here, and to set the ticket to needs review

[mkoeppe]

comment:4

Thanks for this contribution.

We would also like to add CI infrastructure for testing the build on opensuse using Docker. This would follow the same steps as #30044 (for voidlinux).

[sagetrac-git]

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

0ea1e48

build/pkgs/*: add/update distros/opensuse.txt

[sagetrac-git]

Changed commit from e4a917d to 0ea1e48

[jengelh]

Author: Jan Engelhardt

[mkoeppe]

Description changed:

--- 
+++ 
@@ -1 +1,5 @@
-[commit to be attached]
+To test:
+
+```
+tox -e docker-opensuse-standard
+```

[mkoeppe]

Changed branch from u/gh-jengelh/30619 to u/mkoeppe/30619