nixos/nextcloud: updates for nc28

* Always use PHP 8.2: at the time of writing, Nextcloud also suggests to
  use 8.2 rather than 8.3 in the manual for v28.

  One contributing factor is probably that all plugins need new releases
  to declare PHP 8.3 support.

* Fix upgradeWarning for installing v27 now that v28 is out.

* Drop upgrade warning for v24. This one is EOL for quite a while
  already, so right now everybody should've switched (or carefully
  studied the release notes in case they were upgrading from <23.05) and
  we can clean up the module a little bit.

  v25 was dropped not so long ago, so if it's still referenced (because
  somebody didn't declare `services.nextcloud.package` and has
  `system.stateVersion = "22.11";`) it's appropriate to still give a
  specialized error.

0 files changed, 0 insertions, 0 deletions