DNN: test_input_3d is failed on OpenVINO Windows builders #20534
Description
ERROR: test_input_3d (test_dnn.dnn_test)
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Traceback (most recent call last):
File "C:\build\3_4_openvino-win64\opencv\modules\dnn\misc\python\test\test_dnn.py", line 340, in test_input_3d
real_output = net.forward()
error: Unknown C++ exception from OpenCV code
relates #20480
Problem is related to calling of setPreferableBackend() / setPreferableTarget() for the same network.
Test failure is workarounded in #20814 through using dedicated network instances.