Fix simple typo: ther -> the (#9503)
Fix simple typo: ther -> the (#9503)

Closes #9502
bokeh/bokeh,ericmjl/bokeh,bokeh/bokeh,ericmjl/bokeh,bokeh/bokeh,ericmjl/bokeh,ericmjl/bokeh,bokeh/bokeh,ericmjl/bokeh,bokeh/bokeh