Add installing tango-pyaml to docs workflow.

Author: TeresiaOlsson

.github/workflows/documentation.yml

@@ -47,6 +47,7 @@ jobs:
       - name: Install package
         run: |
           python -m pip install '.[doc]'
+          python -m pip install tango-pyaml
           python -m pip install pyaml-cs-oa[tango]
           python -m pip install pyaml-cs-oa[epics]