deps: upgrade Zenoh to 0.11.0-rc.3

The main motivation to make that change is the ability to keep the
Rust version to 1.72.

Indeed, in this version of Zenoh there is no longer an unused dependency
on `Clap` of `zenoh-utils` which — because Clap does not respect SemVer
— forced several crates to be released with Rust 1.74.

* Cargo.lock: update dependencies.
* Cargo.toml:
  - changed the version of the Zenoh crate to 0.11.0-rc.3,
  - `zenoh-plugin-trait` crate: removed the `default-features = false`
    as it no longer applies,
  - `zenoh` crate:
    - removed the `shared-memory` feature,
    - added the `unstable` and `plugins` features.
* tests/zenoh-plugin-zenoh-flow.json: a Zenoh configuration that
  attempts to load Zenoh-Flow as a plugin.
* zenoh-plugin-zenoh-flow/Cargo.toml: removed the `no_mangle` feature
  as it is no longer needed.
* zenoh-plugin-zenoh-flow/src/lib.rs: updated the trait implementation
  to align with Zenoh 0.11.0-rc.3.

Signed-off-by: Julien Loudet <[email protected]>