tests: set rackscale runner only whe it's not multi-node

Signed-off-by: Reto Achermann <achreto@gmail.com>

Author: achreto

kernel/testutils/src/rackscale_runner.rs

@@ -786,12 +786,13 @@ impl<T: Clone + Send + 'static> RackscaleBench<T> {
 
         // Set rackscale appropriately, rebuild if necessary.
         if !is_baseline != test_run.built.with_args.rackscale {
-            eprintln!("\tRebuilding with rackscale={}", !is_baseline,);
+            let is_rackscale = !is_baseline && !test_run.is_multi_node;
+            eprintln!("\tRebuilding with rackscale={}", is_rackscale);
             test_run.built = test_run
                 .built
                 .with_args
                 .clone()
-                .set_rackscale(!is_baseline)
+                .set_rackscale(is_rackscale)
                 .build();
         }