The bundled python interpreter is used instead.

Bug: 1318617
Change-Id: I86c359ad765ecf494a11d199f2e01a711c86d4c2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/3807202Reviewed-by: Gavin Mak <gavinmak@google.com>
Commit-Queue: Brian Ryner <bryner@google.com>