ElasticSearchClientService should not allow both BASIC and API_KEY properties to be set simultaneously

While the ElasticSearchClientService will show/hide Controller Service properties based on the currently selected AuthorizationScheme, it is possible for a user to set BASIC credentials (e.g. Username/Password) then later switch to API_KEY auth without removing the BASIC properties - this leads to multiple Authorization headers being configured in requests to Elasticsearch, which is unexpected.