build(deps-dev): bump pytest-mock from 3.14.1 to 3.15.1 in /clients/python (kubeflow#1691)

Bumps [pytest-mock](https://github.com/pytest-dev/pytest-mock) from 3.14.1 to 3.15.1.
- [Release notes](https://github.com/pytest-dev/pytest-mock/releases)
- [Changelog](https://github.com/pytest-dev/pytest-mock/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-mock@v3.14.1...v3.15.1)

---
updated-dependencies:
- dependency-name: pytest-mock
  dependency-version: 3.15.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]