ui: Minor XML fixes

`tools:context` is unused; fix RTL

app-common/src/main/res/layout/activity_main.xml

@@ -3,8 +3,7 @@
     xmlns:app="http://schemas.android.com/apk/res-auto"
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    tools:context=".ui.MainActivity">
+    android:layout_height="match_parent">
 
     <com.google.android.material.appbar.MaterialToolbar
         android:id="@+id/toolbar"

app-common/src/main/res/layout/fragment_euicc.xml

@@ -25,7 +25,7 @@
         android:id="@+id/fab"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
-        android:layout_marginRight="16dp"
+        android:layout_marginEnd="16dp"
         android:layout_marginBottom="16dp"
         android:src="@drawable/ic_add"
         app:layout_constraintRight_toRightOf="parent"