Merge pull request #19815 from OrestChura:oc/fix_garray_garray_input

modules/gapi/include/opencv2/gapi/cpu/gcpukernel.hpp

@@ -190,6 +190,11 @@ template<> struct get_in<cv::GArray<cv::GScalar> >: public get_in<cv::GArray<cv:
 {
 };
 
+// FIXME(dm): GArray<vector<U>>/GArray<GArray<U>> conversion should be done more gracefully in the system
+template<typename U> struct get_in<cv::GArray<cv::GArray<U>> >: public get_in<cv::GArray<std::vector<U>> >
+{
+};
+
 //FIXME(dm): GOpaque<Mat>/GOpaque<GMat> conversion should be done more gracefully in the system
 template<> struct get_in<cv::GOpaque<cv::GMat> >: public get_in<cv::GOpaque<cv::Mat> >
 {