CalDAV: yearly events alwasy included in current day

[haegar33]

Describe the bug
When refreshing data from my Baikal CalDAV calendar all yearly events (i.e. Birthdays) are embedded in the object of the current day:

Screenshots & Logfiles
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Versions:

• Adapter version: 1.2.0
• JS-Controller version: 3.1.6
• Node version:
• Operating system: Rasbian Lite