Serializable interface deprecated in PHP 8.1

[W1DJM]

Using PHP 8.1.0alpha 3 the following errors get thrown when using BigInteger:

[15-Jul-2021 12:45:34 America/New_York] PHP Deprecated: The Serializable interface is deprecated. Implement __serialize() and __unserialize() instead (or in addition, if support for old PHP versions is necessary) in D:\var\Classes\vendor\phpseclib\phpseclib\phpseclib\Math\BigInteger.php on line 42
[15-Jul-2021 12:45:34 America/New_York] PHP Deprecated: The Serializable interface is deprecated. Implement __serialize() and __unserialize() instead (or in addition, if support for old PHP versions is necessary) in D:\var\Classes\vendor\phpseclib\phpseclib\phpseclib\Math\BigInteger\Engines\GMP.php on line 28
[15-Jul-2021 12:45:34 America/New_York] PHP Deprecated: The Serializable interface is deprecated. Implement __serialize() and __unserialize() instead (or in addition, if support for old PHP versions is necessary) in D:\var\Classes\vendor\phpseclib\phpseclib\phpseclib\Math\BigInteger\Engines\PHP64.php on line 29

The code that is generating the errors is:

$key = [
	'e' => new BigInteger(base64_decode($exponent), 256),
	'n' => new BigInteger(base64_decode($modulus), 256)
];

[terrafrost]

5e29049 should fix this.

Thanks!