Rename userFeedback query param to crashReportModal` to avoid confusion with newer User Feedback widget

[cstavitsky]

Background

• there used to just be one user feedback widget (the crash report modal)
• We have a query param that triggers it, ?userFeedback=true
• now there's a new one
• The query param is now confusing, since it refers to the thing now called the crash report modal, but is easily confused with the new user feedback widget

Suggestion

Rename query param to ?crashReportModal=true