Unregisters a folder or database from an ArcGIS Server site.
RemoveDataStoreItem (connection_file, datastore_type, connection_name)
For a hosting server, provide the server URL or use the MY_HOSTED_SERVICES keyword. For a stand-alone server, an ArcGIS Server connection file (.ags) representing the server with which you want to register the data.
The type of data being unregistered.
The name of the folder or database being unregistered, as it is currently registered with the ArcGIS Server site.
Unregisters a folder from ArcGIS Server that was using the alias "My local data folder".
import arcpy arcpy.RemoveDataStoreItem("GIS Servers/MyConnection.ags", "FOLDER", "My local data folder")
Unregisters a database from ArcGIS Server that was using the alias "MSSQL_Conn".
import arcpy arcpy.RemoveDataStoreItem("https://webadaptorhost.domain.com/webadaptorname", "DATABASE", "MSSQL_Conn")