Merge branch 'renovate/sphinx-rtd-theme-1.x' into 'master'

Update dependency sphinx-rtd-theme to v1

See merge request openappstack/openappstack!532

docs/requirements.txt

@@ -49,7 +49,7 @@ sphinx==4.1.2
     #   sphinx-rtd-theme
 sphinx-design==0.0.12
     # via -r requirements.in
-sphinx-rtd-theme==0.5.2
+sphinx-rtd-theme==1.0.0
     # via -r requirements.in
 sphinxcontrib-applehelp==1.0.2
     # via sphinx