Wrap long content and add max height in popovers
### Problem
In some cases popovers can hold a lot of content which causes it to break out of the card.
| User card | Chart popover in Metrics dashboard |
| ------ | ------ |
|  | |
#### Related discussions
- [Long text captions are breaking UI on metric embed chart on Alert details page](https://gitlab.com/gitlab-org/gitlab/-/issues/225657)
- [Slack thread about user cards](https://gitlab.slack.com/archives/C03MSG8B7/p1594995796462100)
### Proposal
We should wrap content and add overflow on the pop-over so it only extends to a certain max height and then a scroll bar appears.
issue