Add Custom Fields to Posts Widget

- [x] I have searched for similar features requests in both open and closed tickets and cannot find a duplicate.
- [x] The feature is still missing in the latest stable version of Elementor ( Elementor Pro. )

**What problem is your feature request going to solve? Please describe.**
I am using the posts widget to display team members for a business. I have created a custom field to add each team members title / position at the company. I want to display that on each team members card on the team member page.

**Describe the solution you'd like**
It would be cool to have custom fields as an option in the meta data section. Or maybe even have an all together new area in the layout that is "Additional Information" that could be set to any custom field.

**Describe alternatives you've considered**
Right now we are just putting the team members position in the excerpt section. But this is not a great working around for SEO.

Thank you :)