fix: demo data setup w/o territory (#36798)

This can fail because it's translated.
diff --git a/erpnext/selling/doctype/customer/customer.py b/erpnext/selling/doctype/customer/customer.py
index 555db59..d351c3c 100644
--- a/erpnext/selling/doctype/customer/customer.py
+++ b/erpnext/selling/doctype/customer/customer.py
@@ -15,6 +15,7 @@
 from frappe.model.naming import set_name_by_naming_series, set_name_from_naming_options
 from frappe.model.utils.rename_doc import update_linked_doctypes
 from frappe.utils import cint, cstr, flt, get_formatted_email, today
+from frappe.utils.nestedset import get_root_of
 from frappe.utils.user import get_users_with_role
 
 from erpnext.accounts.party import (  # noqa
@@ -80,6 +81,7 @@
 		validate_party_accounts(self)
 		self.validate_credit_limit_on_change()
 		self.set_loyalty_program()
+		self.set_territory_and_group()
 		self.check_customer_group_change()
 		self.validate_default_bank_account()
 		self.validate_internal_customer()
@@ -138,6 +140,12 @@
 					_("{0} is not a company bank account").format(frappe.bold(self.default_bank_account))
 				)
 
+	def set_territory_and_group(self):
+		if not self.territory:
+			self.territory = get_root_of("Territory")
+		if not self.customer_group:
+			self.customer_group = get_root_of("Customer Group")
+
 	def validate_internal_customer(self):
 		if not self.is_internal_customer:
 			self.represents_company = ""
diff --git a/erpnext/setup/demo_data/customer.json b/erpnext/setup/demo_data/customer.json
index 1b47906..5e77e78 100644
--- a/erpnext/setup/demo_data/customer.json
+++ b/erpnext/setup/demo_data/customer.json
@@ -2,19 +2,16 @@
     {
         "doctype": "Customer",
         "customer_group": "Demo Customer Group",
-        "territory": "All Territories",
         "customer_name": "Grant Plastics Ltd."
     },
     {
         "doctype": "Customer",
         "customer_group": "Demo Customer Group",
-        "territory": "All Territories",
         "customer_name": "West View Software Ltd."
     },
     {
         "doctype": "Customer",
         "customer_group": "Demo Customer Group",
-        "territory": "All Territories",
         "customer_name": "Palmer Productions Ltd."
     }
-]
\ No newline at end of file
+]