Set minLines for battery header text

So the header won't grow/shrink when the text changes.

Bug: 64065456
Test: Build
Change-Id: I96bb00e81d677b1efd55afbfe5f23024d6afd71b

res/layout/battery_header.xml

@@ -47,6 +47,7 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginTop="8dp"
+            android:minLines="2"
             android:textAppearance="@android:style/TextAppearance.Material.Small"/>
 
         <TextView