firefox-mobile: refactor tor bootstrap off deleted onboarding path

• Bug 1809998 - Part 1: Refactor CurrentMode to OnboardingAccountObserver - https://github.com/mozilla-mobile/firefox-android/commit/dc33c0942cd8c104a98448933b0400ec6c31c7e8
• Bug 1809998 - Part 2: Refactor Onboarding adapter items in the homepa… - https://github.com/mozilla-mobile/firefox-android/commit/bf66c03ac48fe9af3fbcc4a12c0e8687cdf37b3a
• Bug 1809998 - Part 3: Add an OnboardingView for displaying the list o… - https://github.com/mozilla-mobile/firefox-android/commit/e43f574929bdd54ea6717dac9a3cbfacde520c8c
• Bug 1809998 - Part 4: Refactor OnboardingInteractor from SessionContr… - https://github.com/mozilla-mobile/firefox-android/commit/a69ee66b2957986dab6acd2de2b7bd1e6254728b
• Bug 1809998 - Part 5: Refactor Onboarding from HomeFragment into its … - https://github.com/mozilla-mobile/firefox-android/commit/d2dbf9b847de192a8a355010413c6b927837c7bf

Onboarding radically changed and our current work, a lot in Mode.kt and HomeFragment.kt are no longer triggered, which mean tor does not bootstrap, so tor brow2ser mobile doesn't tor