Bump demisto-py from 3.2.14 to 3.2.15 in /docker/xsoar-tools

Bumps [demisto-py](https://github.com/demisto/demisto-py) from 3.2.14 to 3.2.15.
- [Release notes](https://github.com/demisto/demisto-py/releases)
- [Changelog](https://github.com/demisto/demisto-py/blob/master/CHANGELOG.md)
- [Commits](demisto/demisto-py@v3.2.14...v3.2.15)

---
updated-dependencies:
- dependency-name: demisto-py
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>