Add missing fields from getClusterNodes documentation (backport #17501)

[mergify]

This is an automatic backport of pull request #17501 done by Mergify.
Cherry-pick of 3d40ec3 has failed:

On branch mergify/bp/v1.6/pr-17501
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	both modified:   docs/src/developing/clients/jsonrpc-api.md

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[mergify]

automerge label removed due to a CI failure

[codecov]

Codecov Report

Merging #17502 (3d40ec3) into v1.6 (b06bfee) will increase coverage by 0.0%.
The diff coverage is 54.9%.

❗ Current head 3d40ec3 differs from pull request most recent head 89c59b9. Consider uploading reports for the commit 89c59b9 to get more accurate results

@@            Coverage Diff            @@
##             v1.6   #17502     +/-   ##
=========================================
  Coverage    82.6%    82.6%             
=========================================
  Files         423      425      +2     
  Lines      116481   118840   +2359     
=========================================
+ Hits        96288    98261   +1973     
- Misses      20193    20579    +386