[MINOR] Improve description (#2113)

hudi-client/src/main/java/org/apache/hudi/metrics/Metrics.java

@@ -97,8 +97,7 @@ public class Metrics {
       guage.setValue(value);
     } catch (Exception e) {
       // Here we catch all exception, so the major upsert pipeline will not be affected if the
-      // metrics system
-      // has some issues.
+      // metrics system has some issues.
       LOG.error("Failed to send metrics: ", e);
     }
   }

hudi-examples/src/main/java/org/apache/hudi/examples/common/ExampleDataSchemaProvider.java

@@ -35,6 +35,6 @@ public class ExampleDataSchemaProvider extends SchemaProvider {
 
   @Override
   public Schema getSourceSchema() {
-    return org.apache.hudi.examples.common.HoodieExampleDataGenerator.avroSchema;
+    return HoodieExampleDataGenerator.avroSchema;
   }
 }

hudi-examples/src/main/java/org/apache/hudi/examples/spark/HoodieWriteClientExample.java

@@ -51,8 +51,10 @@ import java.util.stream.Collectors;
  * Simple examples of #{@link HoodieWriteClient}.
  *
  * To run this example, you should
- *   1. For running in IDE, set VM options `-Dspark.master=local[2]`
- *   2. For running in shell, using `spark-submit`
+ * <pre>
+ *   1. For running in IDE, set VM options `-Dspark.master=local[2]`;
+ *   2. For running in shell, using `spark-submit`.
+ *</pre>
  *
  * Usage: HoodieWriteClientExample <tablePath> <tableName>
  * <tablePath> and <tableName> describe root path of hudi and table name