Remove "Go to Settings" CFR

[rtestard]

User proposal

The first step of onboarding should help users discover the Focus value proposition to help ensure users understand the browser value and retain as a result. Pointing users to Settings early on does not seem optimized for new user retention and can also get users to enable settings that they don't realize will cause web breakage - we instead want users to experience Focus with default settings initially before they make-up their minds.

Ideas for Solution

• Remove "Go to Settings" CFR
• Introduce a "Start your private browsing session" CFR that hangs off of the search bar (see UX on https://www.figma.com/file/ahqwL3sByHprH2Rru9R58b/Onboarding?node-id=3775%3A5493) when onboarding screen 2 (https://github.com/mozilla-mobile/focus-ios/issues/3390) closes and the browser appears for the first time
• Remove the CFR if the user touches any area of the screen