### Godot version

4.1.1 stable

### System information

Windows 10

### Issue description

this is the default size loaded on startup 1024 which seems fine but it actually have loaded the default [2048] and ignored the size in project settings
![image](https://github.com/godotengine/godot/assets/53877170/c8c71de7-468a-487f-8e6c-dba1ce0f8fa5)

changing it now to any size will break it 
[2048]
![image](https://github.com/godotengine/godot/assets/53877170/3082ff09-b7d7-41f7-8fbb-813074a54135)

[512]
![image](https://github.com/godotengine/godot/assets/53877170/5ea4620f-52b5-4d0e-a5f5-747e777cd59d)


### Steps to reproduce

change 2d shadow atlas size in project settings while using compatibility renderer. 

### Minimal reproduction project

_
GLuint vertex_array_gl = 0;
				GLuint index_array_gl = 0;
				uint32_t input_mask = 0; 
				if (mesh_instance.is_valid()) {
					mesh_storage->mesh_instance_surface_get_vertex_arrays_and_format(mesh_instance, j, input_mask, vertex_array_gl);
				} else {
					mesh_storage->mesh_surface_get_vertex_arrays_and_format(surface, input_mask, vertex_array_gl);
				}
				index_array_gl = mesh_storage->mesh_surface_get_index_buffer(surface, 0);
				bool use_index_buffer = false;
				glBindVertexArray(vertex_array_gl);
				glBindBuffer(GL_ARRAY_BUFFER, state.canvas_instance_data_buffers[state.current_data_buffer_index].instance_buffers[state.canvas_instance_batches[p_index].instance_buffer_index]);
				uint32_t range_start = state.canvas_instance_batches[p_index].start * sizeof(InstanceData);
				_enable_attributes(range_start, false, instance_count);
				if (index_array_gl != 0) {
					glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_array_gl);
					use_index_buffer = true;
				}
				if (use_instancing) {
					if (instance_buffer == 0) {
						break;
					}
					
					glBindBuffer(GL_ARRAY_BUFFER, instance_buffer);
					glEnableVertexAttribArray(1);
					glVertexAttribPointer(1, 4, GL_FLOAT, GL_FALSE, instance_stride * sizeof(float), CAST_INT_TO_UCHAR_PTR(0));
					glVertexAttribDivisor(1, 1);
					glEnableVertexAttribArray(2);
					glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, instance_stride * sizeof(float), CAST_INT_TO_UCHAR_PTR(4 * 4));
					glVertexAttribDivisor(2, 1);