Normalizing Flows in PyTensor Notebook (#1588)

* nb init

* small cleanup and re-run

* add section to gallery

* final cleanup

* title

* rename

* rename section

Author: juanitorduz

doc/gallery/applications/normalizing_flows_in_pytensor.ipynb

@@ -58,8 +58,9 @@
     "introduction": "Introduction",
     "rewrites": "Graph Rewriting",
     "autodiff": "Automatic Differentiation",
-    "scan": "Looping in Pytensor",
-    "optimize": "Optimization in Pytensor",
+    "scan": "Looping in PyTensor",
+    "optimize": "Optimization in PyTensor",
+    "applications": "Case Studies",
 }