### Godot version

v4.0.beta17.official [c40020513]

### System information

Windows 11, OpenGL (Compatibility), RTX 2060 (31.0.15.2824)

### Issue description

I tried to make a blurred panel for a ui element with texturelod via shader:

```glsl
shader_type canvas_item;

uniform sampler2D SCREEN_TEXTURE : hint_screen_texture, filter_linear_mipmap_anisotropic;
uniform float blur_amount : hint_range(0.0, 5.0);

void fragment() {
	vec4 blurred = textureLod(SCREEN_TEXTURE, SCREEN_UV, blur_amount);
	COLOR = blurred;
}
```

but what I got instead is this:
![image](https://user-images.githubusercontent.com/72286622/217170426-49f6712d-47ef-4c53-b9f1-30d8ad868084.png)

vulkan renderer does not exhibit this issue:
![image](https://user-images.githubusercontent.com/72286622/217170565-a013c712-94f6-49d1-b9ec-091c28a7790b.png)


### Steps to reproduce

1. Add a TextureRect node
2. Add a Panel node to overlay the previously added node
3. Apply the blur shader to the panel node

### Minimal reproduction project

N/A
default: {
			scale = 100;
		} break;
	}
	rt->process_size = size * scale / 100;
	rt->process_size.x = MAX(rt->process_size.x, 1);
	rt->process_size.y = MAX(rt->process_size.y, 1);
	glGenTextures(2, rt->sdf_texture_process);
	glBindTexture(GL_TEXTURE_2D, rt->sdf_texture_process[0]);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RG16I, rt->process_size.width, rt->process_size.height, 0, GL_RG_INTEGER, GL_SHORT, nullptr);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
	GLES3::Utilities::get_singleton()->texture_allocated_data(rt->sdf_texture_process[0], rt->process_size.width * rt->process_size.height * 4, "SDF process texture[0]");
	glBindTexture(GL_TEXTURE_2D, rt->sdf_texture_process[1]);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RG16I, rt->process_size.width, rt->process_size.height, 0, GL_RG_INTEGER, GL_SHORT, nullptr);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 1);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
	GLES3::Utilities::get_singleton()->texture_allocated_data(rt->sdf_texture_process[1], rt->process_size.width * rt->process_size.height * 4, "SDF process texture[1]");
	glGenTextures(1, &rt->sdf_texture_read);
	glBindTexture(GL_TEXTURE_2D, rt->sdf_texture_read);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, rt->process_size.width, rt->process_size.height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);