Not rendering helper if collection "hidden" beside Promise

If you make a simple async helper in conjuction with a meteor collection, during the sync of the collection, the helper is not updated.

I expect the helper to be refreshed once the collection is synced.

- Blaze: `3.0.1`
- Meteor: `3.0.2`

Here is a small code that you explain better the issue.
If you move up the line of `find.fetch` before the async call it's working as expected.
```js
Template.Home.onCreated(() => {
Tracker.autorun(async () => {
const user = await Meteor.userAsync();
Meteor.subscribe('projects', [user?.someProp]); // Help sync Project Meteor Collection
})
})

Template.Home.helpers({
// This is not working as expected
async someHelper(): Promise {

const someAsyncCall = await myFunction();
if (someAsyncCall) {
const projects = Project.find({}).fetch();
console.log(projects.length) // Always 0
return 'yeah';
}

return ''
}
// This is working as expected
async someHelperWorking(): Promise {

const someAsyncCall = await myFunction();
const projects = Project.find({}).fetch();
if (someAsyncCall) {
console.log(projects.length) // Always 10 (The amount subscribed)
return 'yeah';
}

return ''
}
})
```

Tell me if you need more information.

Start by running the provided Blaze 3.0.1 and Meteor 3.0.2 reproduction, comparing the two helpers and the placement of Project.find({}).fetch(). Trace when the async helper is evaluated relative to collection synchronization, then add a regression test showing that the helper refreshes after the subscribed collection is populated.

Written by the indexing model from the issue text.