Follow up on multi-arch failures

[cverna]

When analyzing a failure we can find out that the actual build failed happened in a build-arch job (like ppc64le etc ..) the agent should be able to re-use it's tools to analyze that build-arch failure.

For example:

just analyze https://jenkins-rhcos--prod-pipeline.apps.int.prod-stable-spoke1-dc-iad2.itup.redhat.com/job/build/861/
podman run --rm -v $(pwd):/app:z --env-file .env --entrypoint "python3" coreos-pipeline-assistant /app/cli.py analyze https://jenkins-rhcos--prod-pipeline.apps.int.prod-stable-spoke1-dc-iad2.itup.redhat.com/job/build/861/
/app/cli.py:49: DeprecationWarning: Use `GoogleModel` instead. See <https://ai.pydantic.dev/models/google/> for more details.
  model = GeminiModel('gemini-2.5-flash', provider='google-gla')
[jenkins_core.py:113 -       get_build_info() ] getting build info for build #861
/usr/local/lib/python3.13/site-packages/urllib3/connectionpool.py:1097: InsecureRequestWarning: Unverified HTTPS request is being made to host 'jenkins-rhcos--prod-pipeline.apps.int.prod-stable-spoke1-dc-iad2.itup.redhat.com'. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#tls-warnings
  warnings.warn(
[jenkins_core.py:157 - get_jenkins_build_logs() ] getting build logs for job_name=build build_number=861
/usr/local/lib/python3.13/site-packages/urllib3/connectionpool.py:1097: InsecureRequestWarning: Unverified HTTPS request is being made to host 'jenkins-rhcos--prod-pipeline.apps.int.prod-stable-spoke1-dc-iad2.itup.redhat.com'. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#tls-warnings
  warnings.warn(
[_client.py:1740 - _send_single_request() ] HTTP Request: POST https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent "HTTP/1.1 200 OK"
=== Build Analysis ===
This Jenkins build `build #861` for `c9s` on `x86_64` failed.

The failure occurred because a parallel sub-job, `build-arch #800`, which was building for the `ppc64le` architecture, completed with a `FAILURE` status.

To debug, you'll need to investigate the logs for `build-arch #800` to determine the specific reason for its failure.