[fenix] For https://github.com/mozilla-mobile/fenix/issues/23193 - Remove @color/onboarding_illustration_selected_private_theme redirection

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

@@ -172,7 +172,6 @@
     <color name="swipe_delete_background_private_theme">@color/photonInk20</color>
     <color name="onboarding_card_background_start_gradient_private_theme">@color/photonViolet60</color>
     <color name="onboarding_card_background_end_gradient_private_theme">@color/photonPurple50</color>
-    <color name="onboarding_illustration_selected_private_theme">@color/accent_private_theme</color>
     <color name="onboarding_illustration_deselected_private_theme">#99FBFBFE</color>
     <color name="add_on_private_browsing_exterior_circle_background_private_theme">@color/accent_private_theme</color>
     <color name="add_on_private_browsing_interior_icon_background_private_theme">@color/photonWhite</color>

app/src/main/res/values/styles.xml

@@ -256,7 +256,7 @@
         <item name="swipeDeleteBackground">@color/swipe_delete_background_private_theme</item>
         <item name="onboardingDarkGradientStartBackground">@color/onboarding_card_background_start_gradient_private_theme</item>
         <item name="onboardingDarkGradientEndBackground">@color/onboarding_card_background_end_gradient_private_theme</item>
-        <item name="onboardingSelected">@color/onboarding_illustration_selected_private_theme</item>
+        <item name="onboardingSelected">@color/accent_private_theme</item>
         <item name="onboardingDeselected">@color/onboarding_illustration_deselected_private_theme</item>
         <item name="addOnPrivateBrowsingExteriorCircleBackground">@color/add_on_private_browsing_exterior_circle_background_private_theme</item>
         <item name="addOnPrivateBrowsingInteriorIconBackground">@color/add_on_private_browsing_interior_icon_background_private_theme</item>