Fix RTD builds (#4558)

* Update .readthedocs.yml

* Update requirements-readthedocs.txt

.readthedocs.yml

@@ -1,6 +1,9 @@
-
 # Required
 version: 2
+build:
+  os: "ubuntu-22.04"
+  tools:
+    python: "3.8"
 
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
@@ -13,6 +16,5 @@ formats:
 
 # Optionally set the version of Python and requirements required to build your docs
 python:
-  version: 3.7
   install:
     - requirements: requirements/requirements-readthedocs.txt

requirements/requirements-readthedocs.txt

@@ -4,6 +4,8 @@ hjson
 packaging
 psutil
 py-cpuinfo
-pydantic
+pydantic<2.0.0
+recommonmark
+sphinx_rtd_theme
 torch
 tqdm