Fix compilation issue.

Author: sagarkapare

delta-plugins-common/src/main/java/io/cdap/delta/plugin/mock/MockContext.java

@@ -19,6 +19,7 @@
 import io.cdap.cdap.api.macro.MacroEvaluator;
 import io.cdap.cdap.api.metrics.Metrics;
 import io.cdap.cdap.api.plugin.PluginProperties;
+import io.cdap.delta.api.DeltaPipelineId;
 import io.cdap.delta.api.DeltaSourceContext;
 import io.cdap.delta.api.ReplicationError;
 
@@ -109,6 +110,11 @@ public void putState(String s, byte[] bytes) {
     state.put(s, bytes);
   }
 
+  @Override
+  public DeltaPipelineId getPipelineId() {
+    return new DeltaPipelineId("default", "app", 0L);
+  }
+
   @Override
   public PluginProperties getPluginProperties(String pluginId) {
     return PluginProperties.builder().build();