Changes to Create database

added the new moving enum value to the database/status response property for the response status 201

added the non-success response with the status 409

added the optional property database/down_since to the response with the 201 status

added the optional property database/metrics to the response with the 201 status

added the new optional request property extensions

the database/subscription_id response's property format changed from uuid to no format for status 201

the database/vpc_id response's property format changed from uuid to no format for status 201

added the new resizing enum value to the database/status response property for the response status 201

added the new restoring enum value to the database/status response property for the response status 201

added the optional property database/is_free to the response with the 201 status

added the optional property database/suspended_at to the response with the 201 status

endpoint added