Adjust report abuse layout

What does this MR do and why?

Adjusts Report abuse layout

• Use page heading component
• Remove unnecessary helper text

Screenshots or screen recordings

Before	After

How to set up and validate locally

Report abuse (via a comment, issue, etc), select abuse type, see form

Links

• ✂️ UX Paper Cuts 17.6 → AI part 3, design token... (#474922)