feat(cron api rust): Implement Cron Events Rust

[saibatizoku]

Description

Adds the implementation of a thread-safe Cron Event Queue as a Hermes Runtime Extension.

Related Issue(s)

List the issue numbers related to this pull request.

Closes #146

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[stevenj]

We need tor emove all uses of expect outside the unit tests.
I say in the comments to log. We haven't got a logging infrastructure in hermes yet, but you can put a line where we would log as a comment with a TODO to add logging, and tag the ticket for adding logging to hermes which is #15

Also need to properly add handling for the response to the on_cron event.

[Mr-Leshiy]

LGTM

[minikin]

LGTM