Add support for PHP 8.4

[robbinjanssen]

Description

Add support for PHP 8.4

Motivation and context

Keep the package up to date :-)

How has this been tested?

CI tests should pass.

Checklist:

Go over all the following points, and put an x in all the boxes that apply.

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• I have read the CONTRIBUTING document.
• My pull request addresses exactly one patch/feature.
• My pull request contains a title that can be used as a release note.
• I have added the appropriate labels to my pull request (e.g. breaking-change, new-feature, bugfix).
• I have created a branch for this patch/feature.
• Each individual commit in the pull request is meaningful.
• I have added tests to cover my changes.
• If my change requires a change to the documentation, I have updated it accordingly.

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