fix(dav): fix event birthday alarms not being updated

[tcitworld]

In https://github.com/nextcloud/server/pull/33251 the default offset for a birthday event alarm was changed to 9AM on the day of the event.

However the birthdayEvenChanged method did not account for alarm changes, so it was never propagated to existing birthday events, which were kept on midnight.

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)

[tcitworld]

/backport to stable27

[tcitworld]

/backport to stable26

[tcitworld]

/backport to stable25

[tcitworld]

Should we add a repair job just like RegenerateBirthdayCalendars to fix all existing events? Or just edit the app config value from regeneratedBirthdayCalendarsForYearFix to something like regeneratedBirthdayCalendarsForAlarmFix so that it's triggered again?

[miaulalala]

Should we add a repair job just like RegenerateBirthdayCalendars to fix all existing events? Or just edit the app config value from regeneratedBirthdayCalendarsForYearFix to something like regeneratedBirthdayCalendarsForAlarmFix so that it's triggered again?

Repair step sounds good to me.

[tcitworld]

Rebased

[tcitworld]

/backport to stable28

[skjnldsv]

psalm says