Bug 28462: Remove line breaks in TT tags

Bug 28462: Remove line breaks in TT tags

Same as previous patch for other files.
Looks like the problem exists only with IF.

== test plan ==
1. See the problematic strings in a given language
     git grep "\bIF\b" misc/translator/po | grep -v '#' | grep '\bzh-Hant-TW'
2. update the language
   misc/translator/translate update zh-Hant-TW
3. Recheck the problematic strings, they aren't here anymore
4. Check the diff: git diff
   and search the if's with «/-.* IF » to see how the deleted strings
   look like and that it makes sense.

Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>