chore: handle warnings

Author: jvsena42

app/src/main/res/xml/appwidget_info_price.xml

@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
     android:minWidth="@dimen/appwidget_min_width"
     android:minHeight="@dimen/appwidget_min_height"
     android:targetCellWidth="@integer/appwidget_target_cell_width"
@@ -10,4 +11,5 @@
     android:previewLayout="@layout/appwidget_preview_price"
     android:description="@string/appwidget__price__description"
     android:configure="to.bitkit.appwidget.config.AppWidgetConfigActivity"
-    android:updatePeriodMillis="0" />
+    android:updatePeriodMillis="0"
+    tools:targetApi="31" />