fix: replace cur_frm with frm (bp #27210)

(cherry picked from commit 327071cb90)

Co-authored-by: François de Ryckel <f.deryckel@gmail.com>

erpnext/accounts/doctype/account/account.js

@@ -74,7 +74,7 @@ frappe.ui.form.on('Account', {
 			});
 		} else if (cint(frm.doc.is_group) == 0
 			&& frappe.boot.user.can_read.indexOf("GL Entry") !== -1) {
-			cur_frm.add_custom_button(__('Ledger'), function () {
+			frm.add_custom_button(__('Ledger'), function () {
 				frappe.route_options = {
 					"account": frm.doc.name,
 					"from_date": frappe.sys_defaults.year_start_date,