Update copy in verify step of create group flow

What does this MR do and why?

Part of https://gitlab.com/gitlab-org/growth/team-tasks/-/issues/533/

Addresses !77315 (comment 815053236)

This MR updates the copy in verify step (experimental) of create group flow to let the user know they will not be charged when verifying.

It adds the string You will not be charged during this step. If we ever need to charge you, we will let you know. to the existing paragraph.

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