use html builder (same as during RTD build process)

Author: marscher

.azure/scripts/documentation.yml

@@ -9,7 +9,7 @@ steps:
   displayName: 'Install requirements'
 
 - script: |
-    python -m sphinx -T -b readthedocs -d _build/doctrees-readthedocs -D language=en -W doc build/html
+    python -m sphinx -T -b html -d _build/doctrees-readthedocs -D language=en -W doc build/html
   displayName: 'Check documentation'
 
 - task: CopyFiles@2