Add license scan report and status

[fossabot]

Your FOSSA integration was successful! Attached in this PR is a badge and license report to track scan status in your README.

Below are docs for integrating FOSSA license checks into your CI:

• CircleCI
• TravisCI
• Jenkins
• Other

[koordinator-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[fossabot]

Your license scan is passing -- congrats!

Your badge status is now updated and ready to merge:

[zwzhang0107]

/hold until the license-scan passed

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