Bump openapi-spec-validator from 0.5.5 to 0.5.6

Bumps [openapi-spec-validator](https://github.com/python-openapi/openapi-spec-validator) from 0.5.5 to 0.5.6.
- [Release notes](https://github.com/python-openapi/openapi-spec-validator/releases)
- [Commits](python-openapi/openapi-spec-validator@0.5.5...0.5.6)

---
updated-dependencies:
- dependency-name: openapi-spec-validator
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]