Add stacked Message content variant #809
Description
We want to look into allowing message content to be stacked, so that metadata + avatar are on the same line, and the actual message content is below it, as seen in the following screenshot:
Acceptance criteria:
- Add a prop to allow opting into this new structure
- Adjust the markup as necessary to place metadata + avatar in the same container, and message content separate
- Check whether the current behavior where the avatar scrolls with the message content doesn't occur
Jira Issue: PF-3543