Resolve "Remove ignoring of `merge_requests_require_code_owner_approval` column on projects"

What does this MR do?

Remove the code added in #34636 (closed) to ignore a dropped column.

Screenshots

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

• [-] Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers

Related to #34638 (closed)