Implement audio teaser view tracking in n-tracking

[magsallen]

Implement audio teaser view tracking in n-tracking as it's required by several FT applications.

This code is currently required in the search page, the article page and the stream page. As the audio team is currently winding down, it makes sense to centralise this code so that the tracking events being sent by each application remain consistent without the active oversight of a team.

Example implementation from https://github.com/Financial-Times/next-search-page/pull/264

oTracking.view.init({
    selector: '.o-teaser--audio',
    getContextData: (el) => {
        return {
            componentContentId: el.getAttribute('data-id'),
            component: 'teaser',
            type: 'audio',
            subtype: 'podcast'
        };
    }
});```

[i-like-robots]

I agree with the rationale, but I don't think should be as straightforward as copy and pasting it.

In order to ensure this package remains supportable we need to attach some extra information to it:

• [ ] Which developers know about it?
• [ ] Who owns it?
• [ ] Which tracking spec does this implement?
• [ ] Is there a Chartio dashboard associated with it?
• [ ] Is there a known expiry date? If not, can we add one?