align nac-test 1.2.0, nac-validate 1.2.0 and nac-yaml>=1.1.1 in requirements

[dacasti2mx]

Summary

This PR updates the NaC tooling versions used in the VXLAN ND example repository to keep the environment aligned with the current publicly maintained releases of the Network-as-Code ecosystem.

The update introduces no breaking changes and requires no modifications to the VXLAN ND data model or playbooks.

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Updates in this PR

The requirements.txt is updated to:

nac-yaml>=1.1.1
nac-validate==1.2.0
nac-test==1.2.0

These versions were fully validated in the VXLAN ND public lab.

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nac-yaml 1.1.1 (from 1.0.0)

Enhancements

• Minor internal adjustments and improved compatibility around Vault handling.
• Project tooling updated to the modern uv build system.

Impact / Risk

• No change to YAML merge behavior affecting the VXLAN ND model.
• No required changes to schemas, data-model or roles.
• Safe upgrade.

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nac-validate 1.2.0 (from 1.0.0)

Enhancements

• Adds jmespath as an explicit dependency for internal query improvements.
• More human-readable validation errors (paths now use dictionary keys when possible).
• Improved packaging and logging.

Impact / Risk

• Existing VXLAN ND validation flow works exactly the same.
• No schema, rule, or data-model changes required.
• No functional behavior changes affecting users.

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nac-test 1.2.0

Enhancements

• Updated internal rendering and packaging.
• Keeps the NaC toolchain consistent with nac-validate 1.2.0.

Impact / Risk

• VXLAN ND test templates run exactly as before.
• No changes required to playbooks or templates.

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Testing

Validation was performed end-to-end in the VXLAN ND public lab:

• nac-validate 1.2.0 successfully validates the existing VXLAN ND model.
• nac-test 1.2.0 renders and executes test suites with no changes required.
• Ansible playbooks invoking these tools behave identically to previous versions.

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Conclusion

This PR is a safe, incremental tooling refresh.
There are no new features or behavioral changes that affect the current VXLAN ND model, validation rules, or roles.

It simply aligns the example repository with the current maintained NaC toolchain.

[dacasti2mx]

@juburnet, any comment or modification will be more than welcome.
Thanks.