New API call to merge/update node data

[nuclearcat]

In some situations we might have minor updates for node data, for example we need only to add new data or update if field already exist, but we might now have up to date data. So if we will have such call, we can send only following:

{
"id": "65b218ce985d5bae000b0458",
"state": "done",
"result": "pass",
"data": {
    "new_field": { "new_subfield": "new_data" }
 }
}

Right now we have to fetch updated node data in kbuild for example, because job_id was added, and update node, while with this merge call we can just update state, result and add relevant test data.

[nuclearcat]

Relevant PR fixing issue related to outdated Node data: kernelci/kernelci-core#2344