Update vpython wheel to use latest celab release

What's new in celab:
1. Windows Server 2019 support
2. Python3 compatibility in test infra code
3. Pyperclip support and UTF-8 encode to stdout for UI test

Validation: tryjobs

Change-Id: I8043579229c2bdaa44c64ea5273baeadda097588
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2255120Reviewed-by: Owen Min <zmin@chromium.org>
Commit-Queue: Xiang Ji <jxiang@google.com>
Cr-Commit-Position: refs/heads/master@{#780530}

chrome/test/enterprise/e2e/.vpython

@@ -11,8 +11,8 @@ python_version: "2.7"
 
 wheel: <
   name: "infra/celab/celab/windows-amd64"
-  # Source: https://ci.chromium.org/p/celab/builders/ci/Windows/b8885329255459559360
-  version: "pqWO7Z0XWimF3y7aev5Hwg2h3lYz7_abIqxmm-7hjMkC"
+  # Source: https://ci.chromium.org/p/celab/builders/ci/Windows/b8877198546412479520
+  version: "LveMRjyFsgdFha5yWzmDnWx3MqNWA5j9Xt_brzfxWx8C"
 >
 
 # googleapiclient