[BUGFIX] Simulate user: Fix user selection

This is a follow up fix for #66801 which hides too many users as
an underscore (_) is a wildcard for a single char in SQL LIKE queries.
It also ensures proper quoting of the string value to be compatible with
databases that enforce proper query syntax.

Resolves: #67154
Resolves: #67093
Related: #66801
Releases: master
Change-Id: If0b78cd4e66c3420c832ad98aa5717034f619639
Reviewed-on: http://review.typo3.org/39754


Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Stephan Großberndt <stephan@grossberndt.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Nicole Cordes <typo3@cordes.co>
Tested-by: Nicole Cordes <typo3@cordes.co>