### Godot version

9f9210e60cddb2fa82ce5f7d71fcba340f2edbd1

### System information

Windows 11

### Issue description

I found that one of particles shaders in my project begin working incorrectly after the recent fixes. I've bisected it to 9f9210e60cddb2fa82ce5f7d71fcba340f2edbd1.

Before:
![image](https://github.com/godotengine/godot/assets/3036176/556bb0ed-6214-42ce-b194-8b54b0349b18)


After:
![image](https://github.com/godotengine/godot/assets/3036176/b3fa0b8a-20a6-4c5a-aea7-3e1ec465ea3e)


### Steps to reproduce

Download the provided test project and compare changes with different version.

### Minimal reproduction project

[bug.zip](https://github.com/godotengine/godot/files/12476303/bug.zip)

GDCLASS(GradientTexture2D, Texture2D);
public:
	enum Fill {
		FILL_LINEAR,
		FILL_RADIAL,
		FILL_SQUARE,
	};
	enum Repeat {
		REPEAT_NONE,
		REPEAT,
		REPEAT_MIRROR,
	};
private:
	Ref<Gradient> gradient;
	mutable RID texture;
	int width = 64;
	int height = 64;
	bool use_hdr = false;
	Vector2 fill_from;
	Vector2 fill_to = Vector2(1, 0);
	Fill fill = FILL_LINEAR;
	Repeat repeat = REPEAT_NONE;
	float _get_gradient_offset_at(int x, int y) const;
	bool update_pending = false;
	void _queue_update();
	void _update();