It seems only possible to use git archive after
the changes are commited and this is not very
comfortable during developing. Therefore, changed
to zip instead.

When calling the init function then the Zotero object
is not yet loaded and therefore this line lead to
a undefined variable.

It was easier to move this line instead of using e.g.
```
await Zotero.Schema.schemaUpdatePromise
```
which lead to new problems.