feat: Add setGeneralTimezones method.

[xiCO2k]

This PR adds the capability to change the generalTimezones.

Before

$timezones = new Timezonelist();
$reflected = new \ReflectionClass($timezones);

// @phpstan-ignore-next-line
$property = tap($reflected->getProperty('generalTimezones'))
    ->setAccessible(true)
    ->setValue($timezones, ['UTC']);

return $reflected->getMethod('toArray')->invoke($timezones, false);

After

return Timezonelist::setGeneralTimezones(['UTC'])->toArray(false);

PS: Also found a typo on the facade docblock statis instead of static.

Cheers.

[xiCO2k]

@JackieDo any chance to check this PR?

Thanks.