Update social_emoji module to CKEditor5

Problem/Motivation

The `social_emoji` module contains legacy CKEditor4 JS code.

Steps to reproduce

Go to the `social_emoji` module and check the JS code.

Proposed resolution

Remove the CKeditor4 behavior legacy code.

Remaining tasks

N/A

User interface changes

The `social_emoji` has a emoji behavior only for forms without CKeditor.

API changes

N/A

Data model changes

N/A