Tighten notebook code cell output sandbox and enable it by default (#664)

* Tighten notebook code cell output sandbox

* Enable sandboxnotebookoutputs by default

* Address feedback

package.json

@@ -92,6 +92,7 @@
     "reflect-metadata": "0.1.13",
     "rx-jupyter": "5.5.12",
     "rxjs": "6.6.3",
+    "sanitize-html": "2.3.3",
     "styled-components": "4.3.2",
     "swr": "0.4.0",
     "terser-webpack-plugin": "3.1.0",
@@ -124,6 +125,7 @@
     "@types/react-dom": "17.0.3",
     "@types/react-notification-system": "0.2.39",
     "@types/react-redux": "7.1.7",
+    "@types/sanitize-html": "1.27.2",
     "@types/sinon": "2.3.3",
     "@types/styled-components": "5.1.1",
     "@types/underscore": "1.7.36",