Ensure user token policy ids are unique in server wrapper configuration
Description
The OPC UA specification states that the user token policy ids shall be unique (see UserTokenPolicy policyId description in part 4). It means that for a given policyId, the UserTokenPolicy content is always the same in a server even if it is used in several endpoints. The server should ensure no configuration is used with policyId that is not unique.
Analysis
This property is not verified by the server and the server demo configuration contains non-unique policy id whereas UACTT configuration was not.
Implementation
Fix the demo server configuration to have only unique policy ids. Add a verification in server wrapper configuration check to forbid use of non-unique policy ids.