Fix formatting in CampaignMetadata

Author: daymxn

firebase-inappmessaging/src/main/java/com/google/firebase/inappmessaging/model/CampaignMetadata.java

@@ -17,11 +17,12 @@
 import androidx.annotation.NonNull;
 
 /**
- * <p>Provides the following about any message:</p>
+ * Provides the following about any message:
+ *
  * <ul>
- *    <li>Campaign ID
- *    <li>Campaign Name
- *    <li>Campaign Test Message State
+ *   <li>Campaign ID
+ *   <li>Campaign Name
+ *   <li>Campaign Test Message State
  * </ul>
  */
 public class CampaignMetadata {