Fix calendar handling of pre-1970 birthdates

[TristanDonze]

What is it?

• [x] Bugfix
• [ ] Feature
• [ ] Codebase improvement

Description of the changes in your PR

• Removed lines of codes

Before/After Screenshots/Screen Record

The bug occurred when a contact was created in 'Fossify Contacts' with a birthdate prior to 1970 and saved with the 'Phone Storage (not visible by other apps)' setting. Before the changes, when Calendar synced with the storage, the birth year would automatically default to 1970. After the changes, this behavior has been removed. See screenshot

Profile of a contact who will be 100 years old on May 3, 2024 Before Changes : Event on May 3, 2024: the contact celebrates its 54th anniversary (2024-1970). After Changes : Event on May 3, 2024: the contact celebrates its 100th anniversary (2024-1924).

Fixes the following issue(s)

• Fixes #196

Acknowledgement

• [x] I read the contribution guidelines.