message: Add tf_version to TestResult proto and start storing it with current benchmark
  runs.
diff: @@ -212,4 +212,8 @@ message TestResults {
  // * presubmit: results from oneshot requests.
  // * culprit: results from culprit finder rerun.
  string run_mode = 11;
  +
  + // TensorFlow version this benchmark runs against.
  + // This can be either set to full version or just the major version.
  + string tf_version = 12;
  };
  