Support babylon-vrm-loader babylon.js 5.x

[yamayuski]

https://github.com/BabylonJS/Babylon.js/blob/master/dist/preview%20release/what's%20new.md#500

[YunYouJun]

Babylon is now v5.4.0. Maybe the title can change.

Looking forward to the completion of the adaptation.

[yamayuski]

:tada: This issue has been resolved in version 2.0.0-alpha.1 :tada:

The release is available on:

• GitHub release
• npm package (@alpha dist-tag)

Your semantic-release bot :package::rocket: