Get Databases and Tables from Connection (requires Data Management license)
POST {{base-path}}/sites/{{site-id}}/databaseAndTables/lookup
https://help.tableau.com/current/api/restapi/en-us/REST/restapirefmetadata.htm#getxmldatabasestables
POST {{base-path}}/sites/{{site-id}}/databaseAndTables/lookup
https://help.tableau.com/current/api/restapi/en-us/REST/restapirefmetadata.htm#getxmldatabasestables