Fix error message when --query and --query2 are both used on GET /groups/

--query and --query2 on GET /groups/ are mutually exclusive. Using
both of these options at the same time already failed because the
QueryGroups REST endpoint was always returned when --query2 was
specified and QueryGroups was rejecting --query with:

  "--query" is not a valid option

Change-Id: I89aa4ea8c7f5ed8e354e0cf42635b96aba7ed93e
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/restapi/NeedsParams.java

@@ -28,5 +28,5 @@ public interface NeedsParams {
    *
    * @param params the request parameter
    */
-  void setParams(Multimap<String, String> params);
+  void setParams(Multimap<String, String> params) throws RestApiException;
 }