Update install hook download_url for lakitu-arm64

When the install hook runs for lakitu-arm64, `gsutil ls` will
return stderr `OSError: AF_UNIX path too long` for
app-admin/node-problem-detector and sys-apps/net-tools
even if stdout returns the correct GCS file path.

This CL updates the logic for finding files in GCS by checking
specific string in the returned stderr.

Example generated SBOM: https://storage.cloud.google.com/cos-infra-prod-artifacts-presubmit/lakitu-arm64-release-tryjob/R105-17358.0.0-b9a904aa/sbom-lakitu-arm64-17358.0.0-b9a904aa.json

BUG=b/254334533
TEST=presubmit
RELEASE_NOTE=None

Change-Id: I811cb565520a5e8c37a43366f7b9fe17c0a29c01
Reviewed-on: https://cos-review.googlesource.com/c/third_party/platform/crosutils/+/41009
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
1 file changed