Revert "Fixed bug#9537 - DB.pm 'QueryCondition' removes backslashes (from CustomerUserID/CustomerUserLogin)."

This reverts commit f3f52031afa8ad3282973e8841731306af0f1a2b.

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	CHANGES.md
Merge branch 'rel-3_2' of git.otrs.com:otrs/otrs into rel-3_2

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	CHANGES.md