Fix issue with read the docs due to: https://github.yuuza.net/sphinx-doc/sphinx/issues/9727

.readthedocs.yaml

@@ -0,0 +1,5 @@
+version: 2
+
+python:
+   install:
+   - requirements: docs/requirements.txt

docs/requirements.txt

@@ -0,0 +1,3 @@
+# https://github.yuuza.net/sphinx-doc/sphinx/issues/9727
+sphinx>=4.2.0
+sphinx_rtd_theme>=1.0.0