More javadoc

Author: rpanackal

datamodel/openapi/openapi-core-apache/src/main/java/com/sap/cloud/sdk/services/openapi/apache/apiclient/BaseApi.java

@@ -33,6 +33,9 @@ public abstract class BaseApi
      */
     protected final ApiClient apiClient;
 
+    /**
+     * Default headers to be included in every request.
+     */
     protected final Map<String, String> defaultHeaders = new HashMap<>();
 
     /**