[DOCS] Added the voting node.role value (#48162)

* [DOCS] Added the voting node.role value 

With the elasticsearch.yml option "node.voting_only: true", if you perform a "_cat/nodes" there is a new option for `v` that will display if the node is a voting node.

* [DOCS] Added the voting node.role value

Updated "voting node" to read "voting-only node"

Author: Oofles

docs/reference/cat/nodes.asciidoc

@@ -43,7 +43,7 @@ Valid columns are:
 
 `node.role`, `r`, `role`, `nodeRole`::
 (Default) Roles of the node. Returned values include `m` (master-eligible node),
-`d` (data node), `i` (ingest node), and `-` (coordinating node only).
+`d` (data node), `i` (ingest node), `v` (voting-only node), and `-` (coordinating node only).
 +
 For example, `mdi` indicates a master-eligible data and ingest node.
 
@@ -340,4 +340,4 @@ The API returns the following response:
 id   ip        port  v         m
 veJR 127.0.0.1 59938 {version} *
 --------------------------------------------------
-// TESTRESPONSE[s/veJR/.+/ s/59938/\\d+/ s/[*]/[*]/ non_json]
+// TESTRESPONSE[s/veJR/.+/ s/59938/\\d+/ s/[*]/[*]/ non_json]