Implement operation: delete notarization request

Related to #1 (closed).

• The defined functional operation (see requirements)
• Enforces pre-conditions (these pre-conditions are a source of well-known errors)
• Exposes metrics
• Has a correct OpenAPI specification (that defines well-known errors)
• Has tests for:
  • happy path(s)
  • well-known errors

Specific Requirements:

• CMP.NA.00024 Revocation of Notarization Requests
• CMP.NA.00026 Storing/Update/Deletion of Requests

General Requirements:

• CMP.NA.00013 Notarization Request Endpoint
• CMP.NA.00015 Internal Request Management Endpoint