[HUDI-1305] Added an API to shutdown and remove the metrics reporter. (#2132)

This helps in removing reporter once the test has complete. Prevents log pollution from un-necessary metric logs.

- Added an API to shutdown the metrics reporter after tests.

hudi-client/hudi-client-common/src/test/java/org/apache/hudi/metrics/TestHoodieConsoleMetrics.java

@@ -19,6 +19,7 @@
 package org.apache.hudi.metrics;
 
 import org.apache.hudi.config.HoodieWriteConfig;
+import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -38,6 +39,11 @@ public class TestHoodieConsoleMetrics {
     new HoodieMetrics(config, "raw_table");
   }
 
+  @AfterEach
+  public void stop() {
+    Metrics.shutdown();
+  }
+
   @Test
   public void testRegisterGauge() {
     registerGauge("metric1", 123L);