[WIP][ENHANCEMENT] added methods to retrieve portals and urls from WebspaceManager

__Tasks:__

- [x] test coverage
- [ ] gather feedback for my changes


__Informations:__

| Q             | A
| ------------- | ---
| Tests pass?   | yes
| Fixed tickets | none
| BC Breaks     | none
| Doc           | none
Why don't we index the environments?

i.e. this method could be

````php
if (!isset($this->environments[$type]) {
    throw new \....Exception('...');
}

return $this->environments[$type];
````