rpc: Correctly name arguments #14720

Consistently use the same name to describe arguments in the documentation and add a test that uses the name.

By splitting it up, the changes are easier to potentially backport and also make review easier when we switch to RPCHelpMan.

The tests should pass with or without the changes in src.

Partly stolen from #14459 (More RPC help description fixes by ch4ot1c)

cc @ch4ot1c

utACK https://github.com/bitcoin/bitcoin/pull/14720/commits/fa0815c3005c861ba94b96412e7997c25e7f6788

Concept ACK

Nice cleanup!

Makes sense, though I guess the idea eventually would be to use the just-merged RPCHelpMan here?

The tests should pass with or without the changes in src.

Might make sense to split them out to a commit that goes in before the src changes to make this clear.

By splitting it up, the changes are easier to potentially backport and also make review easier when we switch to RPCHelpMan.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #14411 ([wallet] Restore ability to list incoming transactions by label by ryanofsky)
• #13756 (wallet: "avoid_reuse" wallet flag for improved privacy by kallewoof)
• #12674 (RPC: Support addnode onetry without making the connection priviliged by luke-jr)
• #10593 (Relax punishment for peers relaying invalid blocks and headers by luke-jr)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

utACK fa0815c3005c861ba94b96412e7997c25e7f6788