[FIX]hr_employee_calendar_planning:incorrect hours_per_day

[ChristophAbenthungCibex]

Always using the topmost hr.employee.calendar for hours_per_day may lead to unexpected and incorrect behavior. For example if the date_start and date_end of the topmost calendar are in the future. Then the hours_per_day from the future calendar are taken not from the currently used one. The more specific calendars in regard of date_start and date_end are considered earlier than the less specific ones.
Additionally, added a scheduled action to keep hours_per_day up to date.

How to recreate the problem:

1. Go to Employee and add a hr.employee.calendar
2. Set the date_start for yesterday and end_date for tomorrow
3. Select any resource.calendar
4. Add another hr.employee.calendar
5. Set date_start to the day after tomorrow
6. Select any other resource.calendar
7. Go to the auto generated calendar of that employee
   The hours_per_day are set to the value of the topmost resource.calendar. That calendar should not be used currently. This can lead to incorrect behavior. For example for incorrect calculations of time offs.

[OCA-git-bot]

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