runtime(debian): update debian related runtime files (#13423)

* Update Debian runtime files

Add mantic as a supported Ubuntu release and move buster/kinetic to
unsupported.

Add syntax highlighting for deb822sources filetype.

Add debsources ftplugin to set relevant comment options.

Move common version information to shared/debversions.vim

Closes #11934

Co-authored-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Co-authored-by: James Addison <jay@jp-hosting.net>
Co-authored-by: Viktor Szépe <viktor@szepe.net>
Signed-off-by: James McCoy <jamessan@jamessan.com>

* Add myself as codeowner for Debian-related runtime files

Signed-off-by: James McCoy <jamessan@jamessan.com>

---------

Signed-off-by: James McCoy <jamessan@jamessan.com>
Co-authored-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Co-authored-by: James Addison <jay@jp-hosting.net>
Co-authored-by: Viktor Szépe <viktor@szepe.net>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/ftplugin/debsources.vim b/runtime/ftplugin/debsources.vim
new file mode 100644
index 0000000..cbb4faf
--- /dev/null
+++ b/runtime/ftplugin/debsources.vim
@@ -0,0 +1,16 @@
+" Language:     Debian sources.list
+" Maintainer:   Debian Vim Maintainers <team+vim@tracker.debian.org>
+" Last Change:  2023 Aug 30
+" License:      Vim License
+" URL:          https://salsa.debian.org/vim-team/vim-debian/blob/main/ftplugin/debsources.vim
+
+if exists('b:did_ftplugin')
+  finish
+endif
+let b:did_ftplugin=1
+
+setlocal comments=:#
+setlocal commentstring=#%s
+setlocal formatoptions-=t
+
+let b:undo_ftplugin = 'setlocal comments< commentstring< formatoptions<'