[TEST] use private randomness in InternalTestCluster

Author: s1monw

src/test/java/org/elasticsearch/test/InternalTestCluster.java

@@ -294,7 +294,7 @@ public InternalTestCluster(long clusterSeed,
             builder.put(RecoverySettings.INDICES_RECOVERY_CONCURRENT_SMALL_FILE_STREAMS, RandomInts.randomIntBetween(random, 10, 15));
             builder.put(ThrottlingAllocationDecider.CLUSTER_ROUTING_ALLOCATION_NODE_CONCURRENT_RECOVERIES, RandomInts.randomIntBetween(random, 5, 10));
             builder.put(RecoverySettings.INDICES_RECOVERY_RETRY_DELAY, TimeValue.timeValueMillis(RandomInts.randomIntBetween(random, 10, 25))); // more shared - we need to retry more often
-        } else if (frequently()) {
+        } else if (random.nextInt(100) <= 90) {
             builder.put(RecoverySettings.INDICES_RECOVERY_CONCURRENT_STREAMS, RandomInts.randomIntBetween(random, 3, 6));
             builder.put(RecoverySettings.INDICES_RECOVERY_CONCURRENT_SMALL_FILE_STREAMS, RandomInts.randomIntBetween(random, 3, 6));
             builder.put(ThrottlingAllocationDecider.CLUSTER_ROUTING_ALLOCATION_NODE_CONCURRENT_RECOVERIES, RandomInts.randomIntBetween(random, 2, 5));