[BUGFIX] Misleading label in beuser module

Change the wording of "loginBefore" label from
"Login before"
to
"Logged in before".

This should clarify the meaning of this filter.

Resolves: #49318
Release: 6.2, 6.1, 6.0
Change-Id: I1aa15c054630c3f01859fb9ef2a40f3ca0ffad2b
Reviewed-on: https://review.typo3.org/21566
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn