Add PY3.13 support to test suite

[mlxd]

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Please complete the following checklist when submitting a PR:

• All new features must include a unit test.
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Context: Add test support for PennyLane with Python 3.13.

Description of the Change:

Benefits:

Possible Drawbacks:

Related GitHub Issues:

[github-actions]

Hello. You may have forgotten to update the changelog!
Please edit doc/releases/changelog-dev.md with:

• A one-to-two sentence description of the change. You may include a small working example for new features.
• A link back to this PR.
• Your name (or GitHub username) in the contributors section.