[gtksourceview] Update POTFILES.skip

[Piotr Drąg <piotrdrag src gnome org>]

commit 24d6a31c545c4a8b1e85bacf87daf0f750408082
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Thu Nov 14 14:38:14 2019 +0100

    Update POTFILES.skip

 po/POTFILES.skip | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/po/POTFILES.skip b/po/POTFILES.skip
index 98e31f3f..43884c09 100644
--- a/po/POTFILES.skip
+++ b/po/POTFILES.skip
@@ -47,6 +47,7 @@ data/language-specs/fish.lang
 data/language-specs/forth.lang
 data/language-specs/fortran.lang
 data/language-specs/fsharp.lang
+data/language-specs/ftl.lang
 data/language-specs/gap.lang
 data/language-specs/gdb-log.lang
 data/language-specs/gdscript.lang