Integrate with Sasha's next-analysis scripts

Sasha Levin has started working on some scripts for summarising pull requests and their testing status:

https://git.kernel.org/pub/scm/linux/kernel/git/sashal/next-analysis.git/

This looks like a good candidate for having integration with KCIDB and/or Maestro to flag up test results for the tree being pulled.

Start by reading Sasha Levin's next-analysis repository and locating the existing KCIDB and Maestro integration points in kernelci-core. Define which pull-request and testing-status data should be exchanged and what an end-to-end flag for the pulled tree would demonstrate as done.

Written by the indexing model from the issue text.