fix: Wrap security report comparison in signatures FF

What does this MR do?

With !54608 (merged) we should have wrapped the report comparison under the feature flag but it was missed. This has revealed a significant performance impact that should be addressed, but will be done as a follow-up. For now we are partially reverting the comparison logic within !54608 (merged) and wrapping the new logic within a conditional flag

Related to #329436 (closed)

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
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Security

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