MINOR: Fixing unchecked warning in partition strategy test (#18541)

Reviewers: Viktor Somogyi-Vass <[email protected]>, Chia-Ping Tsai <[email protected]>

Author: apoorvmittal10

share/src/test/java/org/apache/kafka/server/share/fetch/PartitionMaxBytesStrategyTest.java

@@ -23,7 +23,6 @@
 
 import org.junit.jupiter.api.Test;
 
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
@@ -56,7 +55,7 @@ public void testCheckValidArguments() {
             100, partitions, 0));
         // empty partitions set.
         assertThrows(IllegalArgumentException.class, () -> PartitionMaxBytesStrategy.checkValidArguments(
-            100, Collections.EMPTY_SET, 20));
+            100, Set.of(), 20));
         // partitions is null.
         assertThrows(IllegalArgumentException.class, () -> PartitionMaxBytesStrategy.checkValidArguments(
             100, null, 20));