The list-class prop is not being applied correctly when used with scoped styles.

### Describe the bug

The list-class prop is not being applied correctly when used with scoped styles.

### Reproduction

```Vue

export default {
props: {
list: Array,
},
}

.scroller {
height: 100%;
}

.scroller-wrapper {
background-color: red;
}

.user {
height: 32%;
padding: 0 12px;
display: flex;
align-items: center;
}

```

### System Info

```shell
System:
OS: Windows 10 10.0.18363
CPU: (4) x64 Intel(R) Core(TM) i5-7400 CPU @ 3.00GHz
Memory: 3.85 GB / 11.90 GB
Binaries:
Node: 18.16.1 - C:\Program Files\nodejs\node.EXE
Yarn: 1.17.3 - D:\yarn-1.17.3\bin\yarn.CMD
npm: 9.5.1 - C:\Program Files\nodejs\npm.CMD
pnpm: 8.14.0 - C:\Program Files\nodejs\node_global\pnpm.CMD
Browsers:
Chrome: 131.0.6778.86
Edge: Spartan (44.18362.1533.0)
Internet Explorer: 11.0.18362.1
npmPackages:
vite: ^4.5.3 => 4.5.3
vue: 2.6.14 => 2.6.14
vue-virtual-scroller: ^1.1.2 => 1.1.2
```

### Used Package Manager

npm

### Validations

- [X] Read the [docs](https://github.com/Akryum/vue-virtual-scroller/blob/master/packages/vue-virtual-scroller/README.md).
- [X] Check that there isn't [already an issue](https://github.com/Akryum/vue-virtual-scroller/issues) that reports the same bug to avoid creating a duplicate.
- [X] Check that this is a concrete bug. For Q&A open a [GitHub Discussion](https://github.com/Akryum/vue-virtual-scroller/discussions).
- [X] The provided reproduction is a [minimal reproducible example](https://stackoverflow.com/help/minimal-reproducible-example) of the bug.