Incompatible with PHP 7.3

[VarunAgw]

Please test it thoroughly before publishing it to production.

https://www.php.net/manual/en/language.types.declarations.php#language.types.declarations.mixed

The feature is introduced in PHP 8.0, yet it's used widely in the code.

Example error: ( ! ) Fatal error: Uncaught TypeError: Return value of KiteConnect\KiteConnect::getPositions() must be an instance of KiteConnect\mixed, instance of stdClass returned in D:\www\trading\vendor\zerodha\phpkiteconnect\src\KiteConnect.php on line 648

There might be more issues with PHP 7.3. Please test it thoroughly with PHP 7.3.