### Godot version

4.2.dev 80de898d721f952dac0b102d48bb73d6b02ee1e8

### System information

OpenXR

### Issue description

The Godot 3 OpenXR plugin supported obtaining boundary/guardian information in order to obtain play space logic. While we do have a function in the `XRInterface` in Godot 4 that is supposed to retrieve this information (`get_play_area`) it is not implemented on the Godot 4 `OpenXRInterface`.

This logic needs to be ported.

### Steps to reproduce

Call `get_play_area`, be amazed by it not returning data :P

### Minimal reproduction project

Any XR project.
extension_ptrs.ptr() 
	};
	copy_string_to_char_buffer(project_name, instance_create_info.applicationInfo.applicationName, XR_MAX_APPLICATION_NAME_SIZE);
	XrResult result = xrCreateInstance(&instance_create_info, &instance);
	ERR_FAIL_COND_V_MSG(XR_FAILED(result), false, "Failed to create XR instance.");
	
	XrInstanceProperties instanceProps = {
		XR_TYPE_INSTANCE_PROPERTIES, 
		nullptr, 
		0, 
		"" 
	};
	OPENXR_API_INIT_XR_FUNC_V(xrGetInstanceProperties);
	result = xrGetInstanceProperties(instance, &instanceProps);
	if (XR_FAILED(result)) {
		
		print_line("OpenXR: Failed to get XR instance properties [", get_error_string(result), "]");
		runtime_name = "";
		runtime_version = "";
	} else {
		runtime_name = instanceProps.runtimeName;
		runtime_version = OpenXRUtil::make_xr_version_string(instanceProps.runtimeVersion);
		print_line("OpenXR: Running on OpenXR runtime: ", runtime_name, " ", runtime_version);
	}
	for (OpenXRExtensionWrapper *wrapper : registered_extension_wrappers) {
		wrapper->on_instance_created(instance);
	}
	return true;
}
bool OpenXRAPI::get_system_info() {