[core] Correct the UT case about retraction of aggregation merge-engine

Author: 李鹏程

paimon-core/src/test/java/org/apache/paimon/table/PrimaryKeySimpleTableTest.java

@@ -1296,7 +1296,7 @@ public void testAggregationRemoveRecordOnDelete() throws Exception {
         commit.commit(0, write.prepareCommit(true, 0));
         List<String> result =
                 getResult(read, toSplits(snapshotReader.read().dataSplits()), rowToString);
-        assertThat(result).containsExactlyInAnyOrder("+I[1, 1, 2, 2]");
+        assertThat(result).isEmpty();
 
         // 2. Update Before
         write.write(GenericRow.ofKind(RowKind.UPDATE_BEFORE, 1, 1, 2, 2));