Update VeggieSeasons Settings screen to use CupertinoList (#2426)

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- [x] I read the [Flutter Style Guide] _recently_, and have followed its
advice.
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veggieseasons/lib/styles.dart

@@ -107,7 +107,7 @@ abstract class Styles {
 
   static TextStyle settingsGroupFooterText(CupertinoThemeData themeData) =>
       themeData.textTheme.textStyle.copyWith(
-        color: Styles.settingsGroupSubtitle,
+        color: const Color(0xff777777),
         fontSize: 13,
         letterSpacing: -0.08,
       );
@@ -116,7 +116,7 @@ abstract class Styles {
 
   static Color? scaffoldBackground(Brightness brightness) =>
       brightness == Brightness.light
-          ? CupertinoColors.lightBackgroundGray
+          ? CupertinoColors.extraLightBackgroundGray
           : null;
 
   static const frostedBackground = Color(0xccf8f8f8);
@@ -203,12 +203,6 @@ abstract class Styles {
 
   static const Color settingsBackground = Color(0xffefeff4);
 
-  static const Color settingsGroupSubtitle = Color(0xff777777);
-
-  static const Color iconBlue = Color(0xff0000ff);
-
-  static const Color iconGold = Color(0xffdba800);
-
   static const preferenceIcon = IconData(
     0xf443,
     fontFamily: CupertinoIcons.iconFont,
@@ -227,12 +221,6 @@ abstract class Styles {
     fontPackage: CupertinoIcons.iconFontPackage,
   );
 
-  static const checkIcon = IconData(
-    0xf383,
-    fontFamily: CupertinoIcons.iconFont,
-    fontPackage: CupertinoIcons.iconFontPackage,
-  );
-
   static const servingInfoBorderColor = Color(0xffb0b0b0);
 
   static const ColorFilter desaturatedColorFilter =