MAINT: Upgrade to jupyter-book==0.11.2 (#158)

* MAINT: Upgrade to jupyter-book==0.11.2

* FIX: tornado still required to be pinned

Author: mmcky

environment.yml

@@ -6,13 +6,11 @@ dependencies:
   - anaconda=2020.11
   - pip
   - pip:
-    - jupyter-book==0.11.1
-    - sphinx-multitoc-numbering==0.1.3
+    - jupyter-book==0.11.2
     - quantecon-book-theme==0.2.3
     - sphinx-tojupyter==0.1.2
     - sphinxext-rediraffe==0.2.7
     - sphinx-exercise==0.1.1
-    - jupytext==1.11.2
     - ghp-import==1.1.0
     - jupinx==0.2.3
     # Temporary Fixes