Enable Texas Instruments lab for new KernelCI infra

[padovan]

Texas uses a polling method in the legacy system and will continue to do so. We need to provide them instructions on how to that in the new system (and also create upstream docs about it :) ).

This task is to discuss all aspects of the integration and leave trail of for the next few labs connecting in the same way.

[JenySadadia]

Based on the conversation on the mailing list, I believe that TI will poll for available kernel build, fetch it, and run tests in their environment and not within KernelCI.
Here is a possible way of enabling TI for such use case:

1. TI needs to register a user account with API first and get a token
2. Create a new (pipeline) service and make use of PubSub events (the token will be required to poll for events) to get available builds

• The service will poll for completed build nodes
• Event filter will look like: {"kind": "kbuild", "state": "done"}

3. The service can fetch links to build and metadata from Node.artifacts field
4. TI can now run tests within their runtime on the fetched build

[JenySadadia]

Here is a sample service to poll for build events kernelci/kernelci-pipeline#594.
It will make use of a new API PubSub channel called build kernelci/kernelci-api#527.