Updated copy for Duo Pro hand-raise PQL on billings page

What does this MR do and why?

Resolves https://gitlab.com/gitlab-org/gitlab/-/issues/438461.

Updated copy for Duo Pro hand-raise PQL on billings page.

MR acceptance checklist

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Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Setup GDK to simulate SaaS
2. Enable FF with echo "Feature.enable :cs_connect_with_sales" | gdk rails c
3. Visit http://gdk.test:3000/groups/<group_name>/-/billings for a namespace not on a trial (you may need Customer Dot running)
4. See Due Pro card

Related to #438461