l7-three 支持 mapbox 底图

[lvisei]

实现逻辑：

https://docs.mapbox.com/mapbox-gl-js/example/add-3d-model/

代码修改处：

L7/packages/three/src/core/threeRenderService.ts

Lines 75 to 82 in 78a1e5e

	private mapboxCamera(): Camera {
	const mercatorMatrix = new Matrix4().fromArray(
	// @ts-ignore
	this.mapService.map.transform.customLayerMatrix(),
	);
	this.camera.projectionMatrix = mercatorMatrix.multiply(this.cameraTransform);
	return this.camera;
	}

Originally posted by @lvisei in #2435 (comment)