ontrash of nestedset wasn't ideal for employee's usecase (#11876)

diff --git a/erpnext/hr/doctype/employee/employee.py b/erpnext/hr/doctype/employee/employee.py
index 7c9c112..9541b77 100755
--- a/erpnext/hr/doctype/employee/employee.py
+++ b/erpnext/hr/doctype/employee/employee.py
@@ -159,7 +159,7 @@
 			throw(_("Employee cannot report to himself."))
 
 	def on_trash(self):
-		super(Employee, self).on_trash()
+		self.update_nsm_model()
 		delete_events(self.doctype, self.name)
 
 	def validate_prefered_email(self):