[Bug] the documented usage of flock triggers warnings in PHP 8.5

[stof]

Affected page

https://www.php.net/manual/en/function.flock.php#refsect1-function.flock-examples

Issue description

https://wiki.php.net/rfc/marking_return_value_as_important updated flock to mark its return value as NoDiscard. However, the documented usage of the function is precisely discarding the return value of flock($fp, LOCK_UN) when releasing the lock

Steps to reproduce

1. Go to https://www.php.net/manual/en/function.flock.php#refsect1-function.flock-examples
2. Copy the code of the first example
3. Execute that code with PHP 8.5-dev

Suggested fix

The documented usage of the function should correspond to a usage that does not trigger warnings (or the warning should be removed)

[TimWolla]

Related to php/php-src#18235.