owncloud/core

Enhancement: Allow oc_sessionPassphrase cookie to expire with session_lifetime

Before this PR the session cookie oc_sessionPassphrase has expiration time 0 regardless of the value of `session_lifetime` in config.php

Now the behavior will be that after setting `session_lifetime` in config.php will make oc_sessionPassphrase cookie to expire 
in that period of time invalidating the current session and forcing a log out. 
In the other hand, if session_lifetime is not defined or 0, oc_sessionPassphrase will assume its original value before this PR of 0.

https://github.com/owncloud/core/issues/38991
https://github.com/owncloud/core/pull/38992