Error trying to access Tour in live demo

[jcheng5]

https://rstudio.github.io/shinyuieditor/live-demo/

Select a template, then click the Tour App button.

[nstrayer]

Much like #226 this points to needing e2e tests of the tour mode. This one is due to the tour library using global which, when the editor is embedded as a component into an islands architecture app, doesn't exist like it expects. Should be a fairly easy fix in the build config for the website.

[nstrayer]

Oof, turns out I had already dealt with this. The tour mode uses react-floater which hasn't been updated in a while and relies on webpack conventions of putting in a global variable that would typically just be window. The bandaid is to just assign global to window somewhere before the tour code gets run. I already did this in the main versions of the app in the html template but neglected to do it in the website version. Is fixed in #239.