Apply fixed conversation flow mode to Chat Widget

[turnerrainer]

This is an enhancement based on https://github.com/buerokratt/byk-widget-mvp/issues/11 Reference pull requests - https://github.com/buerokratt/byk-widget-mvp/pull/12, https://github.com/buerokratt/byk-widget-mvp/pull/13, https://github.com/buerokratt/byk-widget-mvp/pull/14 The scope of this issue is Bürokratt v2, not MVP

AS A Product Owner I WANT Chatbot conversations to be both text- and fixed conversation flow-based SO THAT I could apply them both according to what's most suitable in given situation

Acceptance Criteria

• [ ] Conversations can be either text- or fixed conversation flow-based depending on how they have been defined in the back-end (Rasa + Ruuter DSLs)

CSA

• [ ] buerokratt/Training-Module#353
• [ ] CSA can add optional selections for End User to choose from

End user

• [ ] buerokratt/Buerokratt-Chatbot#424

DSL

• [ ] Fixed conversation flows must be based on https://github.com/buerokratt/byk-widget-mvp/issues/11 schemas
• [ ] buerokratt/Training-Module#354

[1AhmedYasser]

https://github.com/buerokratt/Buerokratt-Chatbot/issues/424 & https://github.com/buerokratt/byk-widget-mvp/issues/11 is done

Remaining https://github.com/buerokratt/Training-Module/issues/353 & https://github.com/buerokratt/Training-Module/issues/354

To be groomed for further development