Describe the PR
The current implementation of getting a list of packages (listPackages) assumes that a non-empty stderr in the output of go list is an error, regardless of the result of the call, which is not true. Here is an example of a non-empty stderr:

go: downloading github.com/go-sql-driver/mysql v1.8.1
go: downloading github.com/go-errors/errors v1.0.1
go: downloading github.com/go-playground/validator/v10 v10.22.1
...
go: downloading go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.53.0
go: downloading github.com/felixge/httpsnoop v1.0.4

There is no information on errors. This is a legitimate output of additional information.

As a result, we get a non-zero status code without any reason.

Let's rely on the error return, and only add the contents of stderr along with it (preferably removing all lines with go: downloading).