Add render fonts to dev deps

Author: DD Liu

package.json

@@ -74,6 +74,7 @@
     "scratch-blocks": "latest",
     "scratch-l10n": "^3.1.20181129221712",
     "scratch-render": "latest",
+    "scratch-render-fonts": "^1.0.0-prerelease",
     "scratch-storage": "^1.1.0",
     "scratch-svg-renderer": "^0.2.0-prerelease",
     "script-loader": "0.7.2",