Generate and export SPDX3 outputs

[rehsfl]

Changes proposed in this pull request:

• Create an SPDX3 class to construct an SPDX3 JSON document
• Add SPDX3 format to merger_ci so it appears in the output folder
• Add an export option in the Export view of the web dashboard

Status

• READY
• HOLD
• WIP (Work-In-Progress)

How to verify this change

Launch VS (either in SPDX2/3 modes) then:

• Verify that an SPDX3 JSON file is present in the output folder
• Open the web dashboard, then export an SPDX3 JSON file

Pull Request Checklist

Please review and check all that apply before submitting your PR:

• The code compiles and passes all tests
• All new and existing tests are passing
• Documentation has been updated (if applicable)
• Code follows project style guidelines
• No sensitive information is included
• Linked relevant issues (if any)
• Added necessary reviewers

[ValentinBoudevin]

LGTM, great feature. It even work converting a old SPDX2 to modern SPDX3.
Can you add a description in your commits?

[ValentinBoudevin]

LGTM, but next time we will need to do cleaner commits with description.