Shadows keep emoji color when applied to emoji symbols

### Tested versions

-Reproducible in Godot 4.5
-Not Reproducible in Godot 4.4.1 and earlier

### System information

Vulkan(Forward +) - Radeon RX Vega 8

### Issue description

After migration from godot 4.4.1 noticed that my labels that have emoji characters started looking strange. And when i disable shadow - they behave normal.

### Steps to reproduce

Make a label with emoji characters in text, and make them shadow with an offset in LabelSettings

### Minimal reproduction project (MRP)

[label-bug.zip](https://github.com/user-attachments/files/22412956/label-bug.zip)

Start with the attached label-bug.zip minimal reproduction project and compare its behavior in Godot 4.5 with 4.4.1. Trace the LabelSettings shadow path for labels containing emoji characters; done means emoji retain their normal appearance when a shadow offset is applied.

Written by the indexing model from the issue text.