Line profiling modal width

What does this MR do?

• Fixes the width of the line profiling modal (500px => 800px) suitable for most developers,
• Uses the common button design compatible with the Peek library,
• Removes unnecessary overrides over Bootstrap 4's modal.

Are there points in the code the reviewer needs to double check?

No.

Why was this MR needed?

Because the line profiling modal is currently too narrow for most developers (on PCs).

Screenshots (if relevant)

before	after
500px	800px

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• [n/a] Documentation created/updated
• [n/a] API support added
• Tests added for this feature/bug
• Conform by the code review guidelines
  • [n/a] Has been reviewed by a UX Designer
  • Has been reviewed by a Frontend maintainer
  • [n/a] Has been reviewed by a Backend maintainer
  • [n/a] Has been reviewed by a Database specialist
• Conform by the merge request performance guides
• Conform by the style guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• [n/a] Internationalization required/considered
• [n/a] End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #46999 (closed)