resized buffer size to 0 for each scope

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/config/permission/AnnotationProcessor.java

@@ -403,6 +403,7 @@ public class AnnotationProcessor {
                     .getMethod(SWAGGER_ANNOTATIONS_PROPERTIES_KEY), annotatedScopes[i], STRING));
             permissions = (String[])methodHandler.invoke(annotatedScopes[i], scopeClass
                     .getMethod(SWAGGER_ANNOTATIONS_PROPERTIES_PERMISSIONS, null),null);
+            aggregatedPermissions.setLength(0);
             for (String permission : permissions) {
                 aggregatedPermissions.append(permission);
                 aggregatedPermissions.append(" ");