How to get Primary Contact Party ID using Person Number in Groovy Script?

**This post was created as part of a How to Service Request (SR)

Release: 11.13.22.07.0

Summary of the question: We need to get Primary Contact Party ID using person number in Groovy script. The trigger is getting the person number and now we need to get the that employee's party id in groovy script to assign as Primary point of contact in Service Request