🐛 ServiceNow: Incidents / tickets table improvements

### Workspace

servicenow

### 📜 Description

I have some opinionated suggestions for the incidents / tickets table:

### 👍 Expected behavior

1. Latest tickets should be shown on top
2. Resolved or closed tickets should be ignored by default

### 👎 Actual Behavior with Screenshots

1. The table shows the oldest tickets first
2. And it shows also all the resolved and closed tickets

### 👟 Reproduction steps

1. I've created a test instance via the [ServiceNow Developer Portal](https://developer.servicenow.com/dev.do#!/learn/learning-plans/washingtondc/new_to_servicenow/app_store_learnv2_buildmyfirstapp_washingtondc_personal_developer_instances).
2. Installed and configured the ServiceNow plugin and got this:

My experiments are available here:

1. https://github.com/christoph-jerolimov/backstage-experiments/tree/main/servicenow
2. https://github.com/christoph-jerolimov/backstage-experiments/tree/main/servicenow-nfs

I changed `plugins/servicenow/src/components/Servicenow/index.tsx` to:

```tsx
import { themes, UnifiedThemeProvider } from '@backstage/theme';

import { EntityServicenowContent as _EntityServicenowContent } from './EntityServicenowContent';

export const EntityServicenowContent = () => {
return (

);
};
```

And started my experiments with

```bash
yarn start --link ~/git/backstage/community-plugins/workspaces/servicenow
```

### 📃 Provide the context for the Bug.

_No response_

### 👀 Have you spent some time to check if this bug has been raised before?

- [x] I checked and didn't find similar issue

### 🏢 Have you read the Code of Conduct?

- [x] I have read the [Code of Conduct](https://github.com/backstage/community-plugins/blob/main/CODE_OF_CONDUCT.md)

### Are you willing to submit PR?

Yes I am willing to submit a PR!

Start with plugins/servicenow/src/components/Servicenow/index.tsx and follow EntityServicenowContent into the incidents or tickets table implementation. Review the table's data-loading and display configuration, using the linked ServiceNow experiments to reproduce the current ordering and status filtering. Done means newest tickets appear first and resolved or closed tickets are excluded by default.

Written by the indexing model from the issue text.