[CI] Send Platform Along with Failure Information (#163817)

To enable disambiguating the platform later when we look at identifying tests failing at HEAD/flaky tests.

Author: boomanaiden154

.ci/premerge_advisor_upload.py

@@ -23,11 +23,13 @@ def main(commit_sha, workflow_run_number, build_log_files):
  )
  test_failures = generate_test_report_lib.get_failures(junit_objects)
  source = "pull_request" if "GITHUB_ACTIONS" in os.environ else "postcommit"
+ current_platform = f"{platform.system()}-{platform.machine()}".lower()
  failure_info = {
  "source_type": source,
  "base_commit_sha": commit_sha,
  "source_id": workflow_run_number,
  "failures": [],
+ "platform": current_platform,
  }
  if test_failures:
  for name, failure_message in test_failures: