Bug 1915550 - Fix 'Document may not end with a transition' errors in Android documentation. r=android-reviewers,skhan

Differential Revision: https://phabricator.services.mozilla.com/D220533

mobile/android/fenix/docs/Architecture-Decisions.md

@@ -90,5 +90,3 @@ Here's a [state diagram of the MVI architecture](https://staltz.com/img/mvi-unid
 We will experiment with writing new components using MVI unidirectional principles. We will need to take care when passing data between components that we do not override a more authoritative source of truth.
 
 Because all changes can be represented by a single, merged and serialized Observable or Flowable, we should be able to use this for debugging. All ViewStates, Changes, and Actions/Intents will be easily loggable to observe the causes of state issues.
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mobile/android/fenix/docs/architecture-overview.md

@@ -169,5 +169,3 @@ This is where much of the business logic of the app lives. Whenever called by an
 - Interact with some third party manager. Typically these will update their own internal state and then emit changes to an observer, which will be used to update our Store
 
 Controllers can become very complex, and should be unit tested thoroughly whenever their methods do more than delegate simple calls to other objects.
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mobile/android/focus-android/docs/Architecture-Decisions.md

@@ -88,5 +88,3 @@ Focus will support Android versions 5 and higher (API 21+). This decisions is pr
 * At the point of writing this ADR we will cover 73.4% of the Android market with that decision [(*)](https://developer.android.com/about/dashboards/index.html).
 
 * Android 4.4 (KitKat) still covers 17.1%. Those users can't install and use Focus. While UI features can be backported, the extended WebView APIs can not. Only a GeckoView based version of Focus would be able to support Android 4.4 or lower.
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