Hooking update for asset script

Feature Requests
1

[description]
we confirmed that replace does not work in assetscript.
If assetscript has a replace function that matches the schema,
we can freely modify some of the things that squidex automatically handles.

[scenario]
Squidex does not know the mimetype for 3D assets.
When creating or updating assets in assetscript, you can freely modify the extension.

.glb file = MIME type: model/gltf-binary

2

Sorry for the delay. You can actually update the metadata and tags, but I see, that it makes sense to also support the mime type.