
sec.privilegeRemoveRoles( action as String, kind as String, role-names as String[] ) as null
  Removes roles ($role-names) from the roles assigned to the privilege
  ($action,$kind).
  If a privilege identified by ($action,$kind) is not found, an error is 
  returned.
 
  If one of $role-names does not correspond to an existing role,
  an error is returned.
  If the current user is limited to granting only his/her roles,
  and $role is not a subset of the current user's roles, then an error
  is returned. 
  
http://marklogic.com/xdmp/privileges/privilege-remove-roles
	  http://marklogic.com/xdmp/privileges/grant-all-roles orhttp://marklogic.com/xdmp/privileges/grant-my-roles
  This function must be executed against the security database.
// execute this against the security database
 
declareUpdate(); 
const sec = require('/MarkLogic/security.xqy');
 
sec.privilegeRemoveRoles(
    "http://marklogic.com/xdmp/privileges/mypriv", 
    "execute", "Contractor")
  
// Removes the specified privilege from the "Contractor" role.