Allow customer-specific policy compliance dashboard URL template

[marians]

On the Backstage cluster details page, in the "Policy Compliance" component, we want to offer customers to link to their own dashboard.

Mockup:

The URL should be able to adapt to the specific cluster looked at, using some variables.

Variables

• MC_NAME: E. g. gazelle
• BASE_DOMAIN: e. g. gaws.gigantic.io
• ORG_NAME: e. g. demotech
• NAMESPACE: e. g. org-demotech

Examples

• https://grafana.{MC_NAME}.{BASE_DOMAIN}/org1/dashboard-id/?cluster_id={CLUSTER_NAME}
• https://observability.example.com/{MC_NAME}/dashboard-id?cluster_id={CLUSTER_NAME}

Query parameters must be URL-encoded.

I think RFC 6570 - URI Templates might be relevant here.

[marians]

FYI @gusevda