Remove localVue Usage from Feature Flag Tests

What does this MR do?

Removes localVue usage, as it isn't being utilized in these tests. Follow-up from !21564 (comment 262171516).

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