Cleanup: drop matrixbot from translations

langs/ja.json

@@ -185,30 +185,6 @@
         "pickTheme": "開始するには、下のテーマを選択してください。",
         "title": "MapCompleteへようこそ"
     },
-    "matrixbot": {
-        "commands": {
-            "dm": {},
-            "documentation": {
-                "file": {},
-                "inputElement": {},
-                "layer": {},
-                "theme": {},
-                "url_parameter": {},
-                "visualisation": {}
-            },
-            "dream": {},
-            "help": {},
-            "info": {},
-            "language": {},
-            "role": {},
-            "scheme": {},
-            "search": {},
-            "shutdown": {},
-            "tags": {},
-            "welcome": {},
-            "wiki": {}
-        }
-    },
     "move": {
         "inviteToMove": {},
         "reasons": {}