[BUGFIX] Fix broken link to security resources page on typo3.org

Resolves: #69400
Releases: master,6.2
Change-Id: I277aee582c4b9158ded7a2227abd170ad81c96b9
Reviewed-on: http://review.typo3.org/42915


Reviewed-by: Morton Jonuschat <m.jonuschat@mojocode.de>
Tested-by: Morton Jonuschat <m.jonuschat@mojocode.de>
Reviewed-by: Daniel Goerz <ervaude@gmail.com>
Tested-by: Daniel Goerz <ervaude@gmail.com>
Reviewed-by: Jan Helke <typo3@helke.de>
Tested-by: Jan Helke <typo3@helke.de>
Reviewed-by: Andreas Fernandez <typo3@scripting-base.de>
Tested-by: Andreas Fernandez <typo3@scripting-base.de>