Update paho-mqtt requirement from <2 to <3

Updates the requirements on [paho-mqtt](https://github.com/eclipse/paho.mqtt.python) to permit the latest version.
- [Release notes](https://github.com/eclipse/paho.mqtt.python/releases)
- [Changelog](https://github.com/eclipse/paho.mqtt.python/blob/master/ChangeLog.txt)
- [Commits](eclipse-paho/paho.mqtt.python@v0.9...v2.0.0)

---
updated-dependencies:
- dependency-name: paho-mqtt
  dependency-type: direct:production
...

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

pyproject.toml

@@ -56,7 +56,7 @@ classifiers = [
 dependencies = [
   "dataclasses; python_version<'3.7'",
   "importlib-metadata; python_version<'3.8'",
-  "paho-mqtt<2",
+  "paho-mqtt<3",
   "pytest-docker-fixtures<2",
 ]