The ellipsis operator was used as a hack to not need to pass any details
as an argument, but it makes what the end object will actually look like
less obvious. It also makes it impossible to pass an array to details
without getting a nested array.
Fixes#2874
Enhance the `koji-finalize` job implementation to be able to cope with
multiple upload targets being specified for an `OSBuildJob`.
Implement a convenience method `OSBuildJobResult.TargetResultsByName()`
for filtering the target results attached to the job result by their
name. Cover the method with an unit test. And lastly use this method in
the `koji-finalize` job to find the appropriate Koji upload target
results.
This is a preparation for enabling cloud uploads for Koji composes.
The osbuild export is specific to the upload target and different
targets may require using a different export. While osbuild-composer
still does not support multiple exports for osbuild jobs, this prepares
the ground for such support in the future.
The backward compatibility with older implementations of the composer
and workers is kept on the JSON (Un)mashaling level, where the JSON
message is always a super-set of the old and new way of providing the
exports to osbuild job.
Add a new worker client error type `ErrorTargetError` representing that
at least one of job targets failed. The actual target errors are added
to the job detail.
Add a new `OSBuildJobResult.TargetErrors()` method for gathering a slice
of target errors contained within an `OSBuildJobResult` instance. Cover
the method with unit test.
