HADOOP-18574. Changing log level of IOStatistics increment to make the DEBUG logs less noisy (#5223)

Contributed by: Mehakmeet Singh

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/statistics/impl/IOStatisticsStoreImpl.java

@@ -190,7 +190,7 @@ public long incrementCounter(final String key, final long value) {
       return counter.get();
     } else {
       long l = incAtomicLong(counter, value);
-      LOG.debug("Incrementing counter {} by {} with final value {}",
+      LOG.trace("Incrementing counter {} by {} with final value {}",
           key, value, l);
       return l;
     }