fixup opencv_extra-clean

opencv.spec

@@ -67,7 +67,7 @@ URL:            https://opencv.org
 #
 Source0:        %{name}-clean-%{version}.tar.gz
 Source1:        %{name}_contrib-clean-%{version}.tar.gz
-Source2:        https://github.com/opencv/opencv_extra/archive/%{version}/opencv_extra-%{version}.tar.gz
+Source2:        %{name}_extra-clean-%{version}.tar.gz
 Source3:        face_landmark_model.dat.xz
 Source4:        https://github.com/opencv/ade/archive/v0.1.1f.zip
 Source5:        xorg.conf