fix(Set Node): Do not stringify null and undefined (#7313)

Github issue / Community forum post (link here to close automatically):
https://community.n8n.io/t/null-and-undefined-in-string-fields/31060/1

packages/nodes-base/nodes/Set/v2/manual.mode.ts

@@ -191,7 +191,13 @@ export async function execute(
 				);
 			}
 
-			const { name, value } = validateEntry(entry, node, i, options.ignoreConversionErrors);
+			const { name, value } = validateEntry(
+				entry,
+				node,
+				i,
+				options.ignoreConversionErrors,
+				node.typeVersion,
+			);
 			newData[name] = value;
 		}