[fenix] Issue https://github.com/mozilla-mobile/fenix/issues/21714: Login button visibility fix on saved logins page

app/src/main/res/layout/component_saved_logins.xml

@@ -56,7 +56,8 @@
             <androidx.recyclerview.widget.RecyclerView
                 android:id="@+id/saved_logins_list"
                 android:layout_width="match_parent"
-                android:layout_height="match_parent"
+                android:layout_height="0dp"
+                android:layout_weight="1"
                 android:visibility="gone"
                 tools:listitem="@layout/logins_item" />
 
@@ -65,6 +66,7 @@
                 layout="@layout/layout_add_login"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
+                android:layout_weight="0"
                 app:layout_constraintBottom_toBottomOf="parent"
                 app:layout_constraintTop_toBottomOf="@id/saved_logins_list" />