Resolve deprecation warnings on PHP 8.5+

[dwanjuki]

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Changes proposed in this Pull Request:

Cast names (boolean), (integer), (double), and (binary) have been deprecated in PHP 8.5.

Updating (double) cast name to (float).

Resolves notice Non-canonical cast (double) is deprecated, use the (float) cast instead

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Changelog entry

Fixed a PHP deprecation warning that may show on sites running PHP 8.5+.