Fix error in importing eligible registrants for programs with target type set to "Individual"

[gonzalesedwin1123]

If the target type is "Individual", the entitlement manager is "default", and there are no filters defined, the function that imports eligible registrants is getting all records from res.partner.

This includes records with the following:

• is_registrant is null
• is_registrant is set to False

[adriancris]

QA Passed
Working as expected

https://drive.google.com/file/d/1VTh9TZoub7myMONS19Y7giBIpFf7mYLM/view?usp=sharing

[github-actions]

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