[BUG] Not all routes are produced for nested controller with multiple parents
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## Information

- **Version:** 7.13.1
- Packages: `@tsed/swagger`

I use nested controllers that have multiple parent controllers. In version `v6.133.1` tsed would correctly create all possible routes in the OpenAPI Specification for the nested controller. In version `v7.13.1`, however, not all routes are produced.

## Example
I have the following controllers:
```ts
@Controller({
    path: '/domain/:contextID',
    children: [
        CommentController,
    ],
})
export class DomainController {}
```

```ts
@Controller({
    path: '/platform/:platform',
    children: [
        CommentController,
    ],
})
export class PlatformController {}
```

```ts
@Controller({
    path: '/comments',
    children: [FlaggedCommentController],
})
export class CommentController {}
```

```ts
@Controller('')
export class FlaggedCommentController {

    @Get('/flag')
    async list() {}

    @Post('/:commentID/flag')
    async create() {}
}
```

In version `v6.133.1` this would result in the following routes for the `FlaggedCommentController`:
- `/domain/{contextID}/comments/flag`
- `/domain/{contextID}/comments/{commentID}/flag`
- `/platform/{platform}/comments/flag`
- `/platform/{platform}/comments/{commentID}/flag`

However, in version `v7.13.1` I get these routes:
- `/platform/{platform}/comments/flag`
- `/platform/{platform}/comments/{commentID}/flag`

## Acceptance criteria

When all routes are generated for the `FlaggedCommentController`:
- `/domain/{contextID}/comments/flag`
- `/domain/{contextID}/comments/{commentID}/flag`
- `/platform/{platform}/comments/flag`
- `/platform/{platform}/comments/{commentID}/flag`
