chore(python): update dependencies in .kokoro/docker/docs (#757)

Source-Link: https://github.com/googleapis/synthtool/commit/59171c8f83f3522ce186e4d110d27e772da4ba7a
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-python:latest@sha256:2ed982f884312e4883e01b5ab8af8b6935f0216a5a2d82928d273081fc3be562

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
2 files changed