Update request: paho-mqtt 1.6.1 → 2.1.0

[ismarslomic]

• Package name: paho-mqtt

• Latest released version: 2.1.0

• Current version on the unstable channel: 1.6.1

• Current version on the stable/release channel: 1.6.1

• [x] Checked the nixpkgs pull requests

Notify maintainers @dotlambda @adisbladis @mweinelt

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[mweinelt]

We're currently in a breaking changes freeze, and that update is very breaking.

https://github.com/NixOS/nixpkgs/issues/303285