Fix readthedocs build

.readthedocs.yaml

@@ -0,0 +1,22 @@
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+version: 2
+
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3"
+
+sphinx:
+   configuration: docs/conf.py
+formats:
+  - epub
+  - pdf
+  - htmlzip
+
+python:
+  install:
+    - method: pip
+      path: .