Library to abstract health check management/scheduling

[dovydas-an]

Develop alpha version of (Python) library abstracting health check management/scheduling with implementations for K8s, CronJobs.

[Jonas-Puksta-Sensmetry]

Designed the first version of the API and implemented a mock version of it c0e2810

[victor-linroth-sensmetry]

Began implementing the K8s backend.

[victor-linroth-sensmetry]

Continued extending the K8s backend in bc99fb2, 92eb278, bdada4a. It currently has one default template and supports creating cronjobs using the current health-runner image, as well as listing and deleting cronjobs. Updating cronjobs remains to be implemented, and a higher level of configuration when it comes to namespaces, roles, etc is probably needed at some point.

[victor-linroth-sensmetry]

I have started to fix up the error handling a bit, but not finished yet.

[victor-linroth-sensmetry]

Much improved error handling and added support for updating cronjobs in the Kubernetes backend.

[victor-linroth-sensmetry]

Updated the Kubernetes backend so it can find the proper configuration even when deployed in a cluster. Also updated it so it can pass on resource attributes to the OpenTelemetry instrumentation for easier filtering.