update kusari.yml to add in sbom generation config

[pxp928]

## Configuration Options

Add the following options to your `kusari.yaml` file:

```yaml
# Enable SBOM generation on merged PRs (default: false)
sbom_generation_enabled: true

# Optional: Custom component name for the SBOM (default: GitHub repo name "owner/repo")
sbom_component_name: "my-custom-component"

# Optional: Override the SBOM subject name in Kusari Platform
sbom_subject_name_override: "custom-subject-name"

# Optional: Override the SBOM subject version in Kusari Platform
sbom_subject_version_override: "v1.0.0"

Configuration Fields

Field	Type	Default	Description
sbom_generation_enabled	bool	false	Enable SBOM generation when PRs are merged to main/master
sbom_component_name	string	"" (uses repo name)	Custom component name for the SBOM metadata
sbom_subject_name_override	string	""	Override SBOM subject name when uploading to Kusari Platform
sbom_subject_version_override	string	""	Override SBOM subject version when uploading to Kusari Platform