Migrate Bootstrap button to GlButton in MR discussion

What does this MR do?

Screenshots

Location	Before	After
Merge request discussion

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

N/A

Security

N/A

Closes #241058 (closed)