The branches listing API is paginated, even if the documentation does not say
anything about it:
For this reason, the reply was capped to 20 results by default. It turns out
that some repositories just went above that threshold, so the a new branch was
not returned even if it was actually available on the repository.
Increase the items-per-page number and hope nobody will create more than 100
branches in a repository. :P
Signed-off-by: Emanuele Aina <email@example.com>