[fenix] For https://github.com/mozilla-mobile/fenix/issues/21973 - Remove @color/tab_tray_heading_icon_menu_dark_theme redirection

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

@@ -67,7 +67,7 @@
     <color name="tab_tray_item_media_background_normal_theme">@color/photonViolet50</color>
     <color name="tab_tray_heading_icon_normal_theme">@color/tab_tray_heading_icon_dark_theme</color>
     <color name="tab_tray_heading_icon_inactive_normal_theme">@color/tab_tray_heading_icon_inactive_dark_theme</color>
-    <color name="tab_tray_heading_icon_menu_normal_theme">@color/tab_tray_heading_icon_menu_dark_theme</color>
+    <color name="tab_tray_heading_icon_menu_normal_theme">@color/photonLightGrey05</color>
     <color name="tab_tray_item_thumbnail_background_normal_theme">@color/tab_tray_item_thumbnail_background_dark_theme</color>
     <color name="tab_tray_item_thumbnail_icon_normal_theme">@color/tab_tray_item_thumbnail_icon_dark_theme</color>
     <color name="tab_tray_selected_mask_normal_theme">@color/tab_tray_selected_mask_dark_theme</color>

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

@@ -39,7 +39,6 @@
     <color name="tab_tray_item_selected_background_dark_theme">#412E69</color>
     <color name="tab_tray_heading_icon_dark_theme">@color/photonViolet50</color>
     <color name="tab_tray_heading_icon_inactive_dark_theme">@color/photonLightGrey05</color>
-    <color name="tab_tray_heading_icon_menu_dark_theme">@color/photonLightGrey05</color>
     <color name="tab_tray_item_thumbnail_background_dark_theme">@color/photonDarkGrey50</color>
     <color name="tab_tray_item_thumbnail_icon_dark_theme">@color/photonDarkGrey05</color>
     <color name="tab_tray_selected_mask_dark_theme">@color/photonViolet50A32</color>