Update python to 3.11 in Docs CI job (#1821)

Author: Alexsandruss

.ci/pipeline/docs.yml

@@ -50,7 +50,7 @@ jobs:
     displayName: 'System info'
   - task: UsePythonVersion@0
     inputs:
-      versionSpec: '3.9'
+      versionSpec: '3.11'
       addToPath: true
   - script: sudo apt-get update && sudo apt-get install -y clang-format
     displayName: 'apt-get'