Fix Gemma4 shared KV export compatibility for transformer 5.12.0 with older support as well

[dhandhalyabhavik]

What does this PR do?

ov export for gemma4 models failed with recent transformers version 5.12.0 because it has changed internal model implementation of Gemma4. They started using shared_kv_states along with past_key_values. Older 5.5.0 implementation of gemma4 had only past_key_values with shared_kv_states inside it.

This patch adds support for latest transformers as well as old transformers.

Fixes # (issue)
#1785

Before submitting

• [NA] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• [NA] Did you make sure to update the documentation with your changes?
• [NA] Did you write any new necessary tests?

Reference links

https://github.com/huggingface/transformers/blob/v5.12.1/src/transformers/models/gemma4/modeling_gemma4.py#L1234

[HuggingFaceDocBuilderDev]

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[rkazants]

please set MAX_TRANSFORMERS_VERSION=5.12.99 here https://github.com/huggingface/optimum-intel/blob/main/optimum/exporters/openvino/model_configs.py#L1289

the same we need here https://github.com/huggingface/optimum-intel/blob/main/optimum/exporters/openvino/model_configs.py#L3844 both min and max version. It helps to avoid bug issue report from the community