Add support for limiting countries in telephone field

Problem/Motivation

Currently, international mode in Telephone provides support to select preferred countries which will be displayed at the top of list but in many cases the user may need to show just few countries in the list, the JS library already has options excludeCountries
and onlyCountries to support this, just need to add options in UI to configure this.

Steps to reproduce

none

Proposed resolution

Add a field Excluded countries where user can enter which countries to hide, and a checkbox Negate this condition which will negate the exclude condition and only show countries which user has specified in the Excluded countries field.

Remaining tasks

1. Create MR based on proposed solution
2. Write Test
3. Review the changes.