[fix][broker] Fix AvgShedder strategy check (#23156)

(cherry picked from commit 66cc754)

pulsar-broker/src/main/java/org/apache/pulsar/broker/loadbalance/impl/ModularLoadManagerImpl.java

@@ -271,11 +271,11 @@ public void initialize(final PulsarService pulsar) {
             // if the placement strategy is also a load shedding strategy
             // we need to check two strategies are the same
             if (!conf.getLoadBalancerLoadSheddingStrategy().equals(
-                    conf.getLoadBalancerPlacementStrategy())) {
+                    conf.getLoadBalancerLoadPlacementStrategy())) {
                 throw new IllegalArgumentException("The load shedding strategy: "
                         + conf.getLoadBalancerLoadSheddingStrategy()
                         + " can't work with the placement strategy: "
-                        + conf.getLoadBalancerPlacementStrategy());
+                        + conf.getLoadBalancerLoadPlacementStrategy());
             }
             // bind the load shedding strategy and the placement strategy
             loadSheddingPipeline.add((LoadSheddingStrategy) placementStrategy);