[quadrapassel] Update Japanese translation

[Translations User D-L <translations src gnome org>]

commit 3fa912b9a274b0f2a20e28015f3e8f55f6d12142
Author: sicklylife <translation sicklylife jp>
Date:   Sat Feb 29 16:06:45 2020 +0000

    Update Japanese translation

 po/ja.po | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/po/ja.po b/po/ja.po
index a3e6398..2946250 100644
--- a/po/ja.po
+++ b/po/ja.po
@@ -16,7 +16,7 @@ msgstr ""
 "Project-Id-Version: gnome-games gnome-2-32\n"
 "Report-Msgid-Bugs-To: https://gitlab.gnome.org/GNOME/quadrapassel/issues\n";
 "POT-Creation-Date: 2020-02-17 14:05+0000\n"
-"PO-Revision-Date: 2020-01-31 00:00+0900\n"
+"PO-Revision-Date: 2020-02-29 20:30+0900\n"
 "Last-Translator: sicklylife <translation sicklylife jp>\n"
 "Language-Team: Japanese <gnome-translation gnome gr jp>\n"
 "Language: ja\n"
@@ -336,7 +336,7 @@ msgstr "クリーン"
 #. Throw up a dialog
 #: src/quadrapassel.vala:502
 msgid "Unable to change key, as this key already exists"
-msgstr ""
+msgstr "このキーはすでに存在するため変更できません"
 
 #: src/quadrapassel.vala:778
 msgid "Unpause the game"