move mdn-data to dev deps

Author: sprocketc

package-lock.json

@@ -94,6 +94,7 @@
     "karma-chrome-launcher": "3.2.0",
     "karma-cljs-test": "0.1.0",
     "karma-junit-reporter": "2.0.1",
+    "mdn-data": "2.8.0",
     "paper": "0.12.18",
     "paperjs-offset": "1.0.8",
     "perfect-freehand": "1.2.2",
@@ -125,7 +126,6 @@
     "electron-updater": "6.3.0-alpha.6",
     "electron-window-state": "5.0.3",
     "font-scanner": "0.2.1",
-    "mdn-data": "2.8.0",
     "opentype.js": "1.3.4"
   }
 }