Drop match threshold on KDE update detected needle

Got a 95% match in
https://openqa.fedoraproject.org/tests/736374#step/desktop_update_graphical/26

Signed-off-by: Adam Williamson <awilliam@redhat.com>

needles/kde/desktop_package_tool_update-kde-detected-20190918.json

@@ -5,7 +5,8 @@
       "type": "match",
       "height": 18,
       "ypos": 741,
-      "xpos": 779
+      "xpos": 779,
+      "match": 90
     }
   ],
   "properties": [],
@@ -13,4 +14,4 @@
     "DESKTOP-kde",
     "desktop_package_tool_update"
   ]
-}
+}