chore(deps): bump bokeh from 2.1.0 to 2.1.1

Bumps [bokeh](https://github.com/bokeh/bokeh) from 2.1.0 to 2.1.1.
- [Release notes](https://github.com/bokeh/bokeh/releases)
- [Changelog](https://github.com/bokeh/bokeh/blob/2.1.1/CHANGELOG)
- [Commits](bokeh/bokeh@2.1.0...2.1.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>