Update .readthedocs.yaml

* Update .readthedocs.yaml

Updated RTD version to `ubuntu-lts-latest`

* Update .readthedocs.yaml

RTD config fix

.readthedocs.yaml

@@ -7,15 +7,16 @@ version: 2
 
 # Set the version of Python and other tools you might need
 build:
-  os: ubuntu-20.04
+  os: ubuntu-lts-latest
   tools:
     python: "3.10"
   jobs:
     pre_install:
+      - pip install --upgrade pip
       - pip install --upgrade --upgrade-strategy only-if-needed --group doc .
     build:
       html:
-        python -m sphinx -T -b html -d _build/doctrees -D language=en . $READTHEDOCS_OUTPUT/html
+      - python -m sphinx -T -b html -d _build/doctrees -D language=en . $READTHEDOCS_OUTPUT/html
     post_build:
       - echo "Command run at 'post_build' step"
       - echo `date`