Add SLSA generic generator workflow

[Jerad551]

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Description

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addresses
This pull request introduces a new GitHub Actions workflow for generating SLSA provenance files, which helps improve supply chain security by providing verifiable build information. The workflow builds artifacts, computes their hashes, and integrates with the SLSA framework to generate and upload provenance data.

Supply chain security enhancements:

• Added .github/workflows/generator-generic-ossf-slsa3-publish.yml workflow to automate SLSA provenance file generation and uploading, leveraging the OpenSSF SLSA framework for level 3 provenance requirements.
• Included steps to build artifacts, compute their SHA256 hashes, and provide them as subjects for provenance generation, improving traceability and integrity of build outputs.

Integration with external tools:

• Configured the workflow to use third-party actions from the SLSA framework, with appropriate permissions for signing and uploading provenance files to releases.