fix: update deprecated data.query syntax used for stacked charts in example project

[AyushAgrawal-A2]

Description

Changes:

• In example-poject, /charts/stacked-charts/ , sql queries were not working due to deprecated data={date.query} syntax. Updated to data={query}

closes #1394

unable to reproduce issue#1394, truncated date string are working when used as x-axis in stacked bar chart

query used:

```sql needful_things
select
    substr(order_datetime,1,7) as date,
    category as category,
    sum(sales) as sales_usd0
from needful_things.orders
group by 1, 2
```
<BarChart data={needful_things} x=date y=sales_usd0 series=category type=stacked100/>

Checklist

• For UI or styling changes, I have added a screenshot or gif showing before & after
• I have added a changeset
• I have added to the docs where applicable
• I have added to the VS Code extension where applicable

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🦋 Changeset detected

Latest commit: 1efc3f8

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@evidence-dev/components	Patch

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