📌 Temporarily pin jupyter_server<2 to prevent jsonschema error

The latest jupyter_server=2.0.6 version installed via readthedocs requires a version of jsonschema which is incompatible with jupyter-book=0.13, resulting in an error like `pkg_resources.UnknownExtra: jsonschema 3.2.0 has no such extra feature 'format-nongpl'`, see also ProjectPythia/cookbook-template#100 (comment) for details. Applying the workaround from ProjectPythia/cookbook-template#101 for now.

Also remove the ipython!=8.7.0 pin added in d29b4bd, since ipython=8.8.0 is released now.

.readthedocs.yml

@@ -19,10 +19,10 @@ build:
     post_install:
       # Install torchdata=0.4.1 instead of 0.5.0 to prevent AttributeError, see
       # https://github.com/pytorch/data/issues/869
-      # Don't install ipython=8.7.0 to prevent
-      # WARNING, Pygments lexer name 'ipython' is not known, see
-      # https://github.com/ipython/ipython/issues/13845
-      - "pip install torchdata==0.4.1 ipython!=8.7.0"
+      # Install jupyter_server<2 to prevent exception: jsonschema 3.2.0 has no
+      # such extra feature 'format-nongpl', see
+      # https://github.com/ProjectPythia/cookbook-template/issues/100
+      - "pip install torchdata==0.4.1 'jupyter_server<2'"
 
 python:
   install: