build(deps): bump websockets in /tests/ocpp-server in the regular group

build(deps): bump websockets in /tests/ocpp-server in the regular group

Bumps the regular group in /tests/ocpp-server with 1 update: [websockets](https://github.com/python-websockets/websockets).

Updates `websockets` from 15.0 to 15.0.1
- [Release notes](https://github.com/python-websockets/websockets/releases)
- [Commits](https://github.com/python-websockets/websockets/compare/15.0...15.0.1)

---
updated-dependencies:
- dependency-name: websockets
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: regular
...

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