Add ipywidgets javascript (#469)

* Add ipywidgets javascript

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Angus Hollands <goosey15@gmail.com>

docs/conf.py

@@ -42,6 +42,16 @@
 nb_execution_mode = "cache"
 nb_execution_show_tb = "READTHEDOCS" in os.environ
 nb_execution_timeout = 60  # Note: 30 was timing out on RTD
+nb_ipywidgets_js = {
+    "https://cdnjs.cloudflare.com/ajax/libs/require.js/2.3.4/require.min.js": {
+        "integrity": "sha256-Ae2Vz/4ePdIu6ZyI/5ZGsYnb+m0JlOmKPjt6XZ9JJkA=",
+        "crossorigin": "anonymous",
+    },
+    "https://cdn.jsdelivr.net/npm/@jupyter-widgets/html-manager@*/dist/embed-amd.js": {
+        "data-jupyter-widgets-cdn": "https://cdn.jsdelivr.net/npm/",
+        "crossorigin": "anonymous",
+    },
+}
 # nb_render_image_options = {"width": "200px"}
 # application/vnd.plotly.v1+json and application/vnd.bokehjs_load.v0+json
 suppress_warnings = ["mystnb.unknown_mime_type"]