<issue_start><issue_comment>Title: refactor: exclude language in export for rasa
username_0: <!-- description of what you achieved -->

I fixed the domain.yml file of the export for rasa zip.
  - response sequences are filtered based on the selected language and the language tag is removed.
<issue_comment>username_1: A good commit message for this one:
```
fix: export for Rasa: domain contains language information  
```