Data mapper doesn't work with optional field access

[MaryamZi]

Description: $title.

Steps to reproduce:

type Person record {|
    string fName;
    string lName;
    int age?;
|};

type Employee record {|
    int id;
    string name;
    int? age;
|};

function transform(Person person) returns Employee => {
    id: 0,
    name: string `${person.fName} ${person.lName}`,
    age: person?.age
};

Affected Versions: Plugin v4.6.0