[fenix] For https://github.com/mozilla-mobile/fenix/issues/23374 - Update Layer2 dark theme color to DarkGrey30

app/src/main/java/org/mozilla/fenix/theme/FirefoxTheme.kt

@@ -42,7 +42,7 @@ object FirefoxTheme {
 
 private val darkColorPalette = FirefoxColors(
     layer1 = PhotonColors.DarkGrey80,
-    layer2 = PhotonColors.DarkGrey50,
+    layer2 = PhotonColors.DarkGrey30,
     layer3 = PhotonColors.DarkGrey60,
     layerAccent = PhotonColors.Violet40,
     layerNonOpaque = PhotonColors.Violet50A32,

app/src/main/res/values-night/colors.xml

@@ -9,7 +9,7 @@
     <!-- Default Screen, Search, Frontlayer background -->
     <color name="fx_mobile_layer_color_1">@color/photonDarkGrey80</color>
     <!-- Card background, Menu background, Dialog, Banner -->
-    <color name="fx_mobile_layer_color_2">@color/photonDarkGrey50</color>
+    <color name="fx_mobile_layer_color_2">@color/photonDarkGrey30</color>
     <!-- App Bar Top, App Bar Bottom, Frontlayer header -->
     <color name="fx_mobile_layer_color_3" tools:ignore="UnusedResources">@color/photonDarkGrey60</color>
     <!-- App Bar Top (edit), Header (edit) -->