Marks Linux_android new_gallery_opengles_impeller__transition_perf to…

… be unflaky (#144677)

<!-- meta-tags: To be used by the automation script only, DO NOT MODIFY.
{
  "name": "Linux_android new_gallery_opengles_impeller__transition_perf"
}
-->
The test has been passing for [50 consecutive runs](https://data.corp.google.com/sites/flutter_infra_metrics_datasite/flutter_check_test_flakiness_status_dashboard/?p=BUILDER_NAME:%22Linux_android%20new_gallery_opengles_impeller__transition_perf%22).
This test can be marked as unflaky.

.ci.yaml

@@ -2638,7 +2638,6 @@ targets:
   - name: Linux_android new_gallery_opengles_impeller__transition_perf
     recipe: devicelab/devicelab_drone
     presubmit: false
-    bringup: true
     timeout: 60
     properties:
       tags: >