Update RTD to v2 config

Author: A5rocks

.readthedocs.yml

@@ -1,10 +1,17 @@
+version: 2
+
 # https://docs.readthedocs.io/en/latest/yaml-config.html
 formats:
   - htmlzip
   - epub
 
-requirements_file: ci/rtd-requirements.txt
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3"
 
 python:
-  version: 3
-  pip_install: True
+  install:
+    - requirements: ci/rtd-requirements.txt
+    - method: pip
+      path: .