chore(python): add kokoro configs for python 3.11  (#480)

Source-Link: https://github.com/googleapis/synthtool/commit/7197a001ffb6d8ce7b0b9b11c280f0c536c1033a
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-python:latest@sha256:c43f1d918bcf817d337aa29ff833439494a158a0831508fda4ec75dc4c0d0320

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