Show an additional warning text on SaaS for removing the license

What does this MR do and why?

Just give an additional warning text when the user tries to remove the license on GitLab.com.

Closes #362717 (closed)

Screenshots or screen recordings

SaaS	SM
dotcom-2022-08-25_15.49.18	selfmanaged-2022-08-25_11.05.57

How to set up and validate locally

1. Make sure your GDK is running in simulate SaaS mode. You can do that by adding a line export GITLAB_SIMULATE_SAAS=1 to env.runit file in your GDK folder. Do not forget to restart the GDK: gdk restart.
2. Activate your instance by using any activation code.
3. Go to Manage Subscription page on your GDK instance.
4. Click the Remove license button and observe the newly added text.

MR acceptance checklist

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