Add a set of unit tests for openstack telemetry app

Change-Id: Ib5963c61ef0c0302a90a4f30d3dd1f0ec2862aea
diff --git a/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryConfigService.java b/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryConfigService.java
index 156e8ff..51e4cea 100644
--- a/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryConfigService.java
+++ b/apps/openstacktelemetry/api/src/main/java/org/onosproject/openstacktelemetry/api/TelemetryConfigService.java
@@ -17,6 +17,9 @@
 
 import org.onosproject.openstacktelemetry.api.config.TelemetryConfig;
 
+/**
+ * Telemetry configuration service interface.
+ */
 public interface TelemetryConfigService {
 
     /**