Canvas: Fix to run validation on change in nodes

Change-Id: Ie1798e65c83e673c90d7df556729cc509a9d2d9c
diff --git a/apps/canvas/front/src/lib/config.ts b/apps/canvas/front/src/lib/config.ts
index ea7f892..187f51c 100644
--- a/apps/canvas/front/src/lib/config.ts
+++ b/apps/canvas/front/src/lib/config.ts
@@ -275,8 +275,7 @@
 }
 
 function EmptyValidator(nodes: AppNode[]): Message[] {
-	nodes = nodes.filter((n) => n.type !== "network");
-	if (nodes.length > 0) {
+	if (nodes.some((n) => n.type !== "network")) {
 		return [];
 	}
 	return [