Refactor description for the IP allow list field

What does this MR do and why?

Clarify description for the IP allow list input field.

Fixes #362352 (closed)

Screenshots or screen recordings

Before

After

How to set up and validate locally

1. Edit a group, for example: https://gdk.test:3443/groups/flightjs/-/edit
2. Expand Permissions and group features collapsable section

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.