[php] Only use values up to the second accuracy for PHP datetime values

Created by: carmenquan

https://github.com/OpenAPITools/openapi-generator/issues/10548

Description PHP is unable to handle highly precise DateTime Values. While this issue covered most cases, we have a few instances of DateTime which are not handled. (i.e. "2021-10-06T20:17:16.076372256Z")

Example:

print_r(strtotime("2021-10-06T20:17:16.076372256Z")); // => ""
print_r(strtotime("2021-10-06T20:17:16.07637225Z")); // =>  "1633551436"

To fix this we only use up to the second accuracy by trimming the date string. strtotime is only accurate up to number of seconds so this does not result in data loss. https://www.php.net/manual/en/function.strtotime.php

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added Client: PHP Issue: Bug labels

requested review from @root

changed title from Only use values up to the second accuracy for PHP datetime values to [php] Only use values up to the second accuracy for PHP datetime values

mentioned in merge request !11213 (merged)

closed

removed review request for @root