Adding doc requirements

.readthedocs.yml

@@ -0,0 +1,14 @@
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+version: 2
+
+sphinx:
+  configuration: docs/conf.py
+
+build:
+  image: latest
+
+python:
+  version: 3.8
+  install:
+    - requirements: docs-requirements.txt

docs-requirements.txt

@@ -0,0 +1,4 @@
+sphinx~=2.4
+sphinx-rtd-theme~=0.4
+sphinx-autodoc-typehints~=1.10.2
+

tox.ini

@@ -57,6 +57,7 @@ commands =
 [testenv:docs]
 deps =
   -c dev-requirements.txt
+  -c docs-requirements.txt
   sphinx
   sphinx-rtd-theme
   sphinx-autodoc-typehints