FEDX-693-take-2 : GHA OSS changes

[tusharmathur-wk]

Summary

Finish migration to GHA.

• Remove Dockerfile
• Remove skynet.yaml
• Generate an SBOM (see the guide)

Testing

• CI passing
• cyclone DX file attached as an artifact on the GHA build

[aviary3-wk]

Security Insights

No security relevant content was detected by automated scans.

Action Items

• Review PR for security impact; comment "security review required" if needed or unsure

• Verify aviary.yaml coverage of security relevant code

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