Generated by `pyupgrade --py3-plus --keep-percent-format` on all our
Python code except `zthumbor` and `zulip-ec2-configure-interfaces`,
followed by manual indentation fixes.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
The payload for when a build is cancelled was causing an error
because the build result code mapping was missing one of the
codes. This commit also fixes a minor typo in the result codes.