chore(python): update dependencies in /.kokoro (#631)

Source-Link: https://github.com/googleapis/synthtool/commit/db94845da69ccdfefd7ce55c84e6cfa74829747e
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-python:latest@sha256:a8a80fc6456e433df53fc2a0d72ca0345db0ddefb409f1b75b118dfd1babd952

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Victor Chudnovsky <vchudnov@google.com>
3 files changed