how to get RawRequest value on to a testcase property

Use groovy script to get raw request

https://community.smartbear.com/t5/SoapUI-Pro/How-to-get-rawrequest-and-response-test-step-using-context-or/td-p/130837

and set a property value.

https://www.soapui.org/scripting-properties/tips-tricks.html#1-1-Get-and-Set-properties