allow for empty birthday when initially inputting person

[DAcodedBEAT]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Allow empty birthday when initially inputting Person to platform.

Issue ticket number and link

Closes #5985

How should this be manually tested?

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Create a person without providing a birthday

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules