Changes to Retrieves a list of schedulers from database

added the non-success response with the status 400

added the non-success response with the status 403

added the optional property items/connection/fromConnector/methods/items/connector to the response with the 200 status

added the optional property items/connection/fromConnector/methods/items/methodType to the response with the 200 status

added the optional property items/connection/toConnector/methods/items/connector to the response with the 200 status

added the optional property items/connection/toConnector/methods/items/methodType to the response with the 200 status