Enable multiline_comments by default

What does this MR do?

Enables :multiline_comments by default.

For: #221268 (closed)

Screenshots

N/A

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