We often have the need to use rich HTML in dialog messages (to show lists, icons, etc.). Previously, our only option was to wrap the message in an `htmlSafe()` call. This PR adds the ability to pass a component name and model to the dialog, which means that we can write the HTML in regular Ember components.
Example, whereas previously we would do this:
```
this.dialog.deleteConfirm({
message: htmlSafe(`<li>Some text</li>`),
});
```
instead we can now do this:
```javascript
import SecondFactorConfirmPhrase from "discourse/components/dialog-messages/second-factor-confirm-phrase";
...
this.dialog.deleteConfirm({
title: I18n.t("user.second_factor.disable_confirm"),
bodyComponent: SecondFactorConfirmPhrase,
bodyComponentModel: model,
})
```
The model passed to the component is optional and will be available as `@model` in the Handlebars template.