(tech-insights): Integrate notifications into the tech-insights backend

[ivangonzalezacuna]

Hey, I just made a Pull Request!

Make the notifications available as part of the FactRetriever context. Now that this plugin is available, it would make sense to let users be able to use this service to trigger notifications when a check is failing.

The usage of this service will be up to the end user, and no logic has to be implemented into the tech-insights directly.

:heavy_check_mark: Checklist

• [ ] A changeset describing the change and affected packages. (more info)
• [ ] Added or updated documentation
• [ ] Tests for new functionality and regression tests for bug fixes
• [ ] Screenshots attached (for UI changes)
• [ ] All your commits have a Signed-off-by line in the message. (more info)