Insights: display insight creator on the single insight page

[Joelkw]

We've gotten requests from customers to display the insight creator so our users can answer things like:

1. Who created this better version of an insight I was interested in?
2. Who else cares about this topic area?
3. Why did someone create this insight? Has it helped them?

We can expose this information on the single-insight page.

Note: an important consideration is to avoid implying the creator is the owner (because that's not how the system works). Something like a tooltip or original creator or created by: or similar.

/cc @Joelkw @felixfbecker @vovakulikov

[Joelkw]

Customers requesting: https://github.com/sourcegraph/accounts/issues/3439, https://github.com/sourcegraph/accounts/issues/569

[coury-clark]

Note from slack: we should make sure that we display a hover label or something similar that clearly says created by instead of owned to prevent any incorrect assumptions about how the data is calculated

[chwarwick]

We do not have information about whom last edited the insight just the user that created it.

[vovakulikov]

Interesting,

Why did someone create this insight? Has it helped them?

Does this point mean that we should allow to add a short insight description field?. I do remember we used to have a sub titles in the insight card, maybe we should bring this UI back.