Prevent server crash when storage provider operation fails

```
[16:23:34.020] INFO: Transforming asset variant 'sf6v9h6fiw9pj3jw6gqa19ih' with template 'thumbnail-generator' {"severity":"INFO","context":"TransformerTemplateEntity"}
Error: ENOENT: no such file or directory, open 'data/storage/units/p7td1844866zo8zbd843l1ni/aelzdbcrxxs5misa7x82ak4q/s472z5ixmqqh5aw13cen31gv/thumbnail-1.webp'
```