Fix topic info in generic subscription callback using zenoh

[caguero]

🦟 Bug fix

Fixes the topic info in the generic subscription callback. When asking for Topic(), the returned string was containing the partition name and it shouldn't. This only happens using zenoh.

E.g.:

./publisher

and

./subscriber_generic 
Topic: [@/flaco:caguero@/foo]
data: "HELLO"

However, topic should be just /foo. This patch fixes the issue.

Note: The ABI checker job is expected to fail.

Summary

Checklist

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• Added tests
• Updated documentation (as needed)
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• Consider updating Python bindings (if the library has them)
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[azeey]

LGTM!