Merge pull request #25141 from surajshetty3416/fix-get_route_options_for_new_doc

fix: get_route_options_for_new_doc for Project
diff --git a/erpnext/projects/doctype/project/project.js b/erpnext/projects/doctype/project/project.js
index 077011a..c5265e2 100644
--- a/erpnext/projects/doctype/project/project.js
+++ b/erpnext/projects/doctype/project/project.js
@@ -18,8 +18,8 @@
 		};
 	},
 	onload: function (frm) {
-		var so = frappe.meta.get_docfield("Project", "sales_order");
-		so.get_route_options_for_new_doc = function (field) {
+		const so = frm.get_docfield("sales_order");
+		so.get_route_options_for_new_doc = () => {
 			if (frm.is_new()) return;
 			return {
 				"customer": frm.doc.customer,