[Ongoing Alerts] Specify the limit size of the response in API documentation

[fe51]

Hi there,

Using the route alerts, I realize the max response size for /alerts/ongoing is limited to 50

If it can be guessed from the code, it would be useful for the user to have this information directly in the documentation.

I don't know if this information is specific to this route, if not, it would be good documentation practice in the general case.

Thanks a lot,
Happy to discuss it !

[frgfm]

Fully agree, I imagine we're gonna solve this at the same time as #250 👍