collide: protect info print with is_info() check

This prevents an unnecessary sqrt

panda/src/collide/collisionPolygon.cxx

@@ -440,10 +440,12 @@ test_intersection_from_sphere(const CollisionEntry &entry) const {
   LVector3 normal = (has_effective_normal() && sphere->get_respect_effective_normal()) ? get_effective_normal() : get_normal();
 #ifndef NDEBUG
   if (!IS_THRESHOLD_EQUAL(normal.length_squared(), 1.0f, 0.001)) {
-    collide_cat.info()
-      << "polygon within " << entry.get_into_node_path()
-      << " has normal " << normal << " of length " << normal.length()
-      << "\n";
+    if (collide_cat.is_info()) {
+      collide_cat.info()
+        << "polygon within " << entry.get_into_node_path()
+        << " has normal " << normal << " of length " << normal.length()
+        << "\n";
+    }
     normal.normalize();
   }
 #endif