doc: Extract FundTxDoc in rpcwallet #23172

No need to duplicate the documentation for the same field(s) three times.

Fix that by de-duplicating it for the fields: conf_target, estimate_mode, replaceable, and solving_data.

Can be reviewed with --color-moved=dimmed-zebra --color-moved-ws=ignore-all-space.

Rendered diff:

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The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #23202 (wallet: allow psbtbumpfee to work with txs with external inputs by achow101)
• #23201 (wallet: Allow users to specify input weights when funding a transaction by achow101)

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.

ACK fafff132cf4e5c2950d28f63cb4320236d1a5495