feat: compute and upload SBOMs for various generator v3 flavors

[kopernic-pl]

PR checklist

• Read the contribution guidelines.
• Ran the shell script under ./bin/ to update Petstore sample so that CIs can verify the change. (For instance, only need to run ./bin/{LANG}-petstore.sh and ./bin/security/{LANG}-petstore.sh if updating the {LANG} (e.g. php, ruby, python, etc) code generator or {LANG} client's mustache templates). Windows batch files can be found in .\bin\windows\.
• Filed the PR against the correct branch: 3.0.0 branch for changes related to OpenAPI spec 3.0. Default: master.

Description of the PR

This pull request enhances the Docker release workflows by adding automated generation and attachment of Software Bill of Materials (SBOM) files to Docker images, improving supply chain security and transparency. It introduces the use of the anchore/sbom-action for SBOM creation and cosign for attaching SBOMs to images in both the master and 3.0 release workflows.

SBOM Generation and Attachment Enhancements:

• Added steps to generate SBOMs in SPDX-JSON format for all relevant Docker images using the anchore/sbom-action GitHub Action in both .github/workflows/docker-release-master.yml and .github/workflows/docker-release-3.0.yml. [1] [2]
• Introduced installation and usage of cosign to attach the generated SBOMs to the respective Docker images, further automating the supply chain security process. [1] [2]

Workflow Configuration Update:

• Removed the unused branches: [ "master" ] input from the workflow_dispatch trigger in .github/workflows/docker-release-master.yml for cleaner configuration.

[Copilot]

Pull request overview

This PR updates the version to 3.0.0-SNAPSHOT and enhances Docker release workflows by adding automated SBOM (Software Bill of Materials) generation and attachment capabilities for improved supply chain security.

Changes:

• Added SBOM generation using anchore/sbom-action for all Docker images in both master and 3.0 release workflows
• Integrated cosign to attach generated SBOMs to Docker images
• Removed unused branches input from workflow_dispatch trigger in master workflow

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
.github/workflows/docker-release-master.yml	Added SBOM generation and attachment steps for generator and CLI images, removed unused branches configuration
.github/workflows/docker-release-3.0.yml	Added SBOM generation and attachment steps for all v3 Docker images (generator, generator-root, CLI, and minimal variants)

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[daniel-gmc]

Looks ok.