Demo in testnet

[sofiatti]

As a person going through the demo, I want to use Testnet so that I can have a closer experience to the one I would have as a user.

Acceptance Criteria

• Demo DApp uses Testnet instead of running locally.

Please also note:

1. If a conversation about this issue is happening when it is being worked on (i.e., has an assignee),
   the outcomes should be documented here (not in the comments).

Resources:

Add image here.