Remove N+1 in license scanning report comparison

What does this MR do?

This change removes a N+1 that occurs when viewing a diff of license scanning reports. This was caused by fetching the software license policy for each detected license in a report during JSON serialization. I have updated this code to utilize the LicenseCompliance class that loads the necessary reported licenses and software licenses policies more efficiently.

• #208723 (closed)
• !34866 (merged)

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Does this MR meet the acceptance criteria?

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