available_processors field in CAT Nodes

[piotrsulkowski-elastic]

Cat nodes REST action will return an extra field:
available_processors

Part of elastic/elasticsearch#134692

• Wait for available_processors field in CAT Nodes elasticsearch#135936

[github-actions]

Following you can find the validation changes against the target branch for the APIs.

API	Status	Request	Response
cat.nodes	🟢	11/11 → 12/12	11/11 → 12/12
cat.segments	🟢 → 🔴	9/9 → 9/10	9/9 → 10/10
index	🟢	1437/1437 → 1440/1440	1439/1439 → 1442/1442
indices.close	🟢	50/50 → 51/51	50/50 → 51/51
indices.create	🔴	1358/1382 → 1373/1397	1382/1382 → 1397/1397
indices.refresh	🟢	328/328 → 329/329	328/328 → 329/329
xpack.usage	🔴	47/47	2/43 → 1/43

You can validate these APIs yourself by using the make validate target.

[pquentin]

Thanks! LGTM.