Store data about the current rawhide release in bodhi

[AdamSaleh]

On https://bodhi.fedoraproject.org/releases/ page it is not explicitly stated which of the releases is current rawhide. We should make this explicit. This will allow us to use the endpoint in our scripts instead of relying on pdc.

[mattiaverga]

I think we already have this: the release which have branch=rawhide is Rawhide.

[mattiaverga]

Closing per the above comment