MAINT: fix RTD (#107)

Author: mmcky

.readthedocs.yml

@@ -5,12 +5,17 @@
 # Required
 version: 2
 
+# Set the OS, Python version and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.11"
+
 # Build documentation in the docs/ directory with Sphinx
 sphinx:
   configuration: docs/source/conf.py
 
 python:
-  version: 3.7
   install:
     - method: pip
       path: .