### Godot version

4.1.1

### System information

windows 11, mobile renderer

### Issue description

On Mobile Vulkan renderer, the clear color is 50% lighter than expected

See steps to reproduce and Minimal reproduction project below.

The box and background have the same color on Forward+ and compatibility, but not on Mobile
happens also in runtime on exported project, not only in editor preview

Images of the same scene from
compatibility:
![compatibility](https://github.com/godotengine/godot/assets/11915378/a874fa86-c16f-43ef-aed7-c2066b770ac1)
Forward+:
![forward](https://github.com/godotengine/godot/assets/11915378/e416f9a6-dfd4-4c47-bbc2-b552ca58f83c)
Mobile:
![mobile](https://github.com/godotengine/godot/assets/11915378/e28e2db8-f7c3-47e2-8c0a-44ce937c9270)


### Steps to reproduce

 - add a CSGBox3D with "unshaded" shading, and albedo of #545454
 - add environment with Background = Custom color and color of #545454

Box and background are not the same color

### Minimal reproduction project

[bg_color.zip](https://github.com/godotengine/godot/files/12174822/bg_color.zip)

RID tex = gi.voxel_gi_instance_get_texture(p_voxel_gi_instances[i]);
				if (!tex.is_valid()) {
					tex = default_tex;
				}
				u.ids.write[i] = tex;
			} else {
				u.ids.write[i] = default_tex;
			}
		}
		uniforms.push_back(u);
	}
	{
		RD::Uniform u;
		u.binding = 8;
		u.uniform_type = RD::UNIFORM_TYPE_STORAGE_BUFFER;
		RID cb = p_cluster_buffer.is_valid() ? p_cluster_buffer : default_vec4_xform_buffer;
		u.append_id(cb);
		uniforms.push_back(u);
	}
	*/
	{
		RD::Uniform u;
		u.binding = 9;
		u.uniform_type = RD::UNIFORM_TYPE_TEXTURE;
		RID texture;
		if (rb.is_valid() && rb->has_texture(RB_SCOPE_BUFFERS, RB_TEX_BACK_DEPTH)) {
			texture = rb->get_texture(RB_SCOPE_BUFFERS, RB_TEX_BACK_DEPTH);
		} else if (is_multiview) {
			texture = texture_storage->texture_rd_get_default(RendererRD::TextureStorage::DEFAULT_RD_TEXTURE_2D_ARRAY_DEPTH);
		} else {