Update readthedocs guidelines based on

https://blog.readthedocs.com/migrate-configuration-v2/

docs/guides/readthedocs.md

@@ -32,11 +32,36 @@ $ make html
 ```
 This generates a simple preview of your documentation (less advanced than rtd) in the folder ```_build```. You can open ```_build/index.html``` in your browser to navigate the preview.
 
+* Add **```.readthedocs.yaml```** to your repository. To configure rtd, you will need to include a file like below.
+
+```yaml
+# Read the Docs configuration file for Sphinx projects
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# 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/conf.py
+
+# Specify the requirements file
+python:
+   install:
+   - requirements: requirements.txt
+```
+
 ## On readthedocs.org
 
 * **Create an account** on https://readthedocs.org (the easiest is to link it to your github account), it you don't already have one.
 * **Add a project** linked to your GitHub/GitLab repository.
-* **Add requirements file** by specifying ```requirements.txt``` under Admin > Advanced Settings -> Requirements file.
+* **Add .readthedocs.yaml** by specifying ```.readthedocs.yaml``` under Admin > Advanced Settings ->  Path for ```.readthedocs.yaml.```
 
 ## Edit your documentation