remove phone_ext as a distinct field

[samuelsov]

If you add a phone + extension in a profile and add it to you contact layout, it will display the phone with extension + the extension label as a distinct field as seen in the screenshot 👍

This PR removes the unecessary labels.

[colemanw]

@samuelsov interesting - so ext is always printed with the phone number already?

[samuelsov]

@colemanw Yes exactly, this is already working like that in core.