webadmin: translated string broken into two lines

[zh_CN][Admin Portal] Translated string of 'Last' broken into two
lines in the 'Enabled Filters' field of 'Edit Cluster Policy' dialog.

Change-Id: Iae00929423d617117158c5ca3e5f942eaa3a98de
Bug-Url: https://bugzilla.redhat.com/1001415
Signed-off-by: Gilad Chaplik <gchaplik@redhat.com>