Enh/apply rector set to apps

[come-nc]

Summary

1. Apply current rector configuration to apps folder
2. Bump rector/rector and nextcloud/rector to latest version
3. Add NextcloudSets::NEXTCLOUD_25 to configuration
4. Run rector on apps folder again

You can note that \OC::$server->get calls are correctly replaced but not \OC::$server->query ones, that’s an oversight of the Set and will need to be fixed upstream.
Apart from that the changes look sound to me.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

[ChristophWurst]

👍 for caldav/carddav

[come-nc]

            // Deprecated since 20.0.0
            new LegacyGetterToOcpServerGet('getUserManager', 'OCP\User\IManager'),
            // Deprecated since 20.0.0
            new LegacyGetterToOcpServerGet('getGroupManager', 'OCP\Group\IManager'),

Those 2 are wrong, should be 'OCP\IUserManager' and 'OCP\IGroupManager'.
Should be fixed upstream.

[come-nc]

            // Deprecated since 20.0.0 Use 'get(\OCP\Files\AppData\IAppDataFactory')->get($app) instead
            new LegacyGetterToOcpServerGet('getAppDataDir', 'OCP\Files\IAppData'),

This is wrong in 25 set. For this PR it can easily be fixed manually I think.
We should still remove or fix this part of the set upstream.