[FEATURE] Possibility to set sessionTimeout for Frontend Users

Currently it was only possible to set the session timeout for the backend users
You can define the sessionTimeout with the new configuration option
$GLOBALS['TYPO3_CONF_VARS']['FE']['sessionTimeout'].

Resolves: #78695
Releases: master
Change-Id: I628ccc4448230af6dd2bf1533777375ef7e5624d
Reviewed-on: https://review.typo3.org/50654


Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Benni Mack <benni@typo3.org>
Tested-by: Benni Mack <benni@typo3.org>