[py] Migrate services/viz PRESUBMIT

Bug: 1212052
Change-Id: I942216ef0606e8f2305ffcd022a960918e6a6440
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2957261
Commit-Queue: Jonathan Backer <[email protected]>
Auto-Submit: Josip Sokcevic <[email protected]>
Reviewed-by: Jonathan Backer <[email protected]>
Cr-Commit-Position: refs/heads/master@{#892141}

Author: sokcevicG

Diff for: services/viz/PRESUBMIT.py

@@ -4,6 +4,9 @@
 
 """Top-level presubmit script for services/viz."""
 
+USE_PYTHON3 = True
+
+
 def CheckChangeOnUpload(input_api, output_api):
   import sys
   original_sys_path = sys.path