[stubsabot] Bump paho-mqtt to 2.0.*

[github-actions[bot]]

Release: https://pypi.org/pypi/paho-mqtt/2.0.0 Homepage: http://eclipse.org/paho Repository: https://github.com/eclipse/paho.mqtt.python Diff: https://github.com/eclipse/paho.mqtt.python/compare/v1.6.1...v2.0.0

Stubsabot analysis of the diff between the two releases:

• Total lines of Python code added: 5638.
• Total lines of Python code deleted: 3471.

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