Make check dummy inputs import conditional in quantizer

[eaidova]

What does this PR do?

continuation of story with broken onnx on windows
from #1048

site-packages\onnx\__init__.py", line 77, in <module>
    from onnx.onnx_cpp2py_export import ONNX_ML
ImportError: DLL load failed while importing onnx_cpp2py_export: A dynamic link library (DLL) initialization routine failed.

returns when user import
from optimum.intel.openvino import OVModelForCausalLM

[HuggingFaceDocBuilderDev]

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