This method is thread-safe.
the security token
Gets a security token from the OKE Proxymux service
the security token, which is basically a JWT token string
Return a claim embedded in the security token
the name of the claim
the value of the claim or null if unable to find
Gets a security token. If there is already a valid token cached, it will be returned. Else this will make a call to the OKE Proxymux service to get a new token, using the provided suppliers.