fix: allow only system manager

Co-authored-by: Suraj Shetty <13928957+surajshetty3416@users.noreply.github.com>

frappe/core/doctype/document_naming_rule/document_naming_rule.py

@@ -33,5 +33,6 @@ class DocumentNamingRule(Document):
 
 @frappe.whitelist()
 def update_current(name, new_counter):
+	frappe.only_for('System Manager')
 	frappe.db.set_value('Document Naming Rule', name, 'counter', new_counter)
 	frappe.db.commit()