hydra-notify: fixup printing of build IDs

Used to print:

sending notifications for build Hydra::Model::DB::Builds=HASH(0x124cf960)->id...

Now it prints:

sending notifications for build 123...

Created by  Your Name  on August 16, 2021
2HCWJE5WNCO66RVMAIUG4RYYG3ZCOAGHZMFNCQQPKH6FG3DN3RTQC
Change contents