[devicelab] fix motog4 tests and update comment. (#144410)

Fixes https://github.com/flutter/flutter/issues/144406

The A02 have also been running Vulkan for quite a while.

.ci.yaml

@@ -2638,14 +2638,15 @@ targets:
 
   # linux motog4 benchmark
   # Moto G4, Impeller (OpenGL)
-  - name: Linux_android new_gallery_impeller__transition_perf
+  - name: Linux_android new_gallery_opengles_impeller__transition_perf
     recipe: devicelab/devicelab_drone
     presubmit: false
+    bringup: true
     timeout: 60
     properties:
       tags: >
         ["devicelab", "android", "linux"]
-      task_name: new_gallery_impeller__transition_perf
+      task_name: new_gallery_opengles_impeller__transition_perf
 
   # Pixel 7 Pro, Impeller (Vulkan)
   - name: Linux_pixel_7pro new_gallery_impeller_old_zoom__transition_perf
@@ -2668,7 +2669,7 @@ targets:
         ["devicelab", "android", "linux", "pixel", "7pro"]
       task_name: new_gallery_impeller__transition_perf
 
-  # Samsung A02, Impeller (OpenGL)
+  # Samsung A02, Impeller (Vulkan)
   - name: Linux_samsung_a02 new_gallery_impeller__transition_perf
     recipe: devicelab/devicelab_drone
     presubmit: false