Async getData() returns the value of parent node instead of the child node.

### Description

Hello!

When I call the async `getData()` method, it returns the snapshot of the parent, not the actual child.

### Reproducing the issue

Create `User` node and two nodes inside of it: `id`, `name`.

- User
-- id : testId
-- name: testName

Call: `let userId = try! await Database.database().reference().child("User").child("id").getData().value`

It returns 2 key-value pairs **id="testId"**, **name="testName"**. But not the `id` only.

### Firebase SDK Version

10.17.0

### Xcode Version

15.1

### Installation Method

Swift Package Manager

### Firebase Product(s)

Database

### Targeted Platforms

iOS

### Relevant Log Output

```shell
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```

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