[BUGFIX] Fix unsafe URL removal in EXT:felogin

A comma can be a valid char inside a url and must not used as
delimiter.

Resolves: #75915
Releases: master, 7.6
Change-Id: I0eb3c6389b5d28e96b981217d09c2fef5dbf331d
Reviewed-on: https://review.typo3.org/49255


Tested-by: Bamboo TYPO3com <info@typo3.com>
Reviewed-by: Sascha Egerer <sascha@sascha-egerer.de>
Reviewed-by: Benni Mack <benni@typo3.org>
Reviewed-by: Frederic Gaus <frederic.gaus@flagbit.de>
Reviewed-by: Daniel Goerz <ervaude@gmail.com>
Reviewed-by: Stefan Neufeind <typo3.neufeind@speedpartner.de>
Reviewed-by: Jan Helke <typo3@helke.de>
Tested-by: Benni Mack <benni@typo3.org>