add .readthedocs.yaml file to correct build error

Author: Andrew Delman

.readthedocs.yaml

@@ -0,0 +1,29 @@
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the version of Python and other tools you might need
+build:
+  os: ubuntu-22.04
+    tools:
+      python: "3.7"
+        # You can also specify other tool versions:
+        # nodejs: "19"
+        # rust: "1.64"
+        # golang: "1.19"
+
+# Build documentation in the docs/ directory with Sphinx
+sphinx:
+  configuration: doc/conf.py
+
+# If using Sphinx, optionally build your docs in additional formats such as PDF
+# formats:
+  - pdf
+
+# Optionally declare the Python requirements required to build your docs
+python:
+  install:
+  - requirements: requirements.txt