Add Toggle on Feature Flags Table

What does this MR do?

Adds a toggle to the feature flag table to allow users to globally toggle the flag on or off, final frontend work for #13416 (closed)

Screenshots

feature_flag_toggle

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