Add .readthedocs.yaml

Read the Docs requires a version 2 configuration file
to prevent build failures by September 25, 2023. [1]

[1]: https://linaro.atlassian.net/browse/TFC-462

Signed-off-by: Arthur She <arthur.she@linaro.org>
Change-Id: I11b44ee7103efc601f1e6840188ecae0e4f1a726
diff --git a/.readthedocs.yaml b/.readthedocs.yaml
new file mode 100644
index 0000000..99c8a87
--- /dev/null
+++ b/.readthedocs.yaml
@@ -0,0 +1,19 @@
+# Read the Docs configuration file for MkDocs projects
+# 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: "3.11"
+
+mkdocs:
+  configuration: mkdocs.yml
+
+# Optionally declare the Python requirements required to build your docs
+python:
+  install:
+  - requirements: requirements.txt