Readthedocs: Don't let notebook failures pass silently

Adds both to conf.py:

nb_execution_allow_errors = False
nb_execution_raise_on_error = True

To make sure that when one of the (tutorial) notebooks fails, the Readthedocs also fails and doesn't continue silently.

See https://myst-nb.readthedocs.io/en/latest/computation/execute.html#error-reporting-warning-vs-failure

docs/conf.py

@@ -113,6 +113,8 @@
 
 nb_execution_timeout = 60
 nb_execution_mode = "cache"
+nb_execution_allow_errors = False
+nb_execution_raise_on_error = True
 
 # -- Options for HTML output ----------------------------------------------
 

docs/tutorials/intro_tutorial.ipynb

@@ -90,15 +90,19 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
-   "metadata": {},
-   "outputs": [],
+   "metadata": {
+    "jupyter": {
+     "is_executing": true
+    }
+   },
    "source": [
     "# SKIP THIS CELL unless running in colab\n",
     "\n",
     "%pip install --quiet mesa\n",
     "# The exclamation points tell jupyter to do the command via the command line"
-   ]
+   ],
+   "outputs": [],
+   "execution_count": null
   },
   {
    "cell_type": "markdown",
@@ -323,7 +327,8 @@
    "outputs": [],
    "source": [
     "starter_model = MoneyModel(10)\n",
-    "starter_model.step()"
+    "starter_model.step()\n",
+    "starter_model.method_doesnt_exist()"
    ]
   },
   {