Tweak: Custom help link on contact buttons

[gabriel-glo]

PR Checklist

• The commit message follows our guidelines: https://github.com/elementor/elementor/blob/master/.github/CONTRIBUTING.md

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

Summary

This PR can be summarized in the following changelog entry:

• Updated help link for Contact Buttons widget

Description

An explanation of what is done in this PR

• Changed the default help link for Contact Buttons widget and its variations to a main Elementor help page.

Test instructions

This PR can be tested by following these steps:

• Add Contact Buttons widget and/or any of its variations in the editor
• Check that the Need Help link in the sidebar panel links to https://elementor.com/help/

Quality assurance

• I have tested this code to the best of my abilities
• I have added unittests to verify the code works as intended
• Docs have been added / updated (for bug fixes / features)

Fixes #