Update webmock requirement from ~> 1.18.0 to ~> 3.13.0
Update webmock requirement from ~> 1.18.0 to ~> 3.13.0

Updates the requirements on [webmock](https://github.com/bblimke/webmock) to permit the latest version.
- [Release notes](https://github.com/bblimke/webmock/releases)
- [Changelog](https://github.com/bblimke/webmock/blob/master/CHANGELOG.md)
- [Commits](https://github.com/bblimke/webmock/compare/v1.18.0...v3.13.0)

---
updated-dependencies:
- dependency-name: webmock
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>
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