Add compact JSON output for scancode

[AyanSinhaMahapatra]

This PR adds a new compact JSON output to minimize scan results filesize by ensuring this option skips duplicate and non-essential attributes. This implements the following for making the scan results compact:

1. remove all duplicated/inline data present in multiple levels (example: removes license detection matches in resource-levels and only keeps top-level unique license detections which makes sure data for a detection is only present once)
2. skip all duplicated codebase/resource attributes (example: keep only one license expression, instead of both scancode/spdx expressions)
3. skip all large/non-essential codebase/resource attributes (example: remove description, license text, diagnostics and other fields, which can be fetched from the original file too if required)
4. remove all empty attributes recursively (keep only the key/value pairs which are non-empty)

Fixes #4555

Tasks

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