Fix: Removed :mixed return type hint as it requires PHP8.0

[james-mckinnon]

Explanation

This change removes the :mixed return type hint for PHP7.4 Compatibility (as it was introduced in PHP8.0)

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Changes to Core Features:

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[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.