Use `comment_cookie_lifetime` filter when removing comment cookies for consistency

[akshaykungiri]

Currently, the wp_set_comment_cookies() function uses the comment_cookie_lifetime filter only when setting cookies, but not when removing them.

This leads to a minor inconsistency: developers filtering comment_cookie_lifetime may expect the same value to apply in both cases, particularly when setting a past timestamp to delete cookies.

### Proposed Enhancement

This patch ensures consistency by applying the same comment_cookie_lifetime filter when calculating the $past value for cookie removal:

php
$past = time() - apply_filters( 'comment_cookie_lifetime', YEAR_IN_SECONDS );

[akshaykungiri]

Created patch.

[johnbillion]

Thanks for the report @akshaykungiri but the cookie lifetime has no relevance here because the cookie's expiry date is being set to a date in the past in order to invalidate it. The lifetime doesn't need to be taken into account.

Cheers!