Make AccountId deserialization accept prefixes larger than 1 byte

[arrudagates]

This fixes the issue described in #2685 however it doesn't properly solve it in a clean manner. A perfect solution would be to somehow retrieve the prefix length from the current chain and use that as the offset for the account id byte array.

[tomaka]

Thanks! Could you add an entry in bin/wasm-node/CHANGELOG.md as well?

[github-actions]

twiggy diff report

Difference in .wasm size before and after this pull request.

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 Delta Bytes │ Item
─────────────┼──────────────────────────────────────────────────────────────────────────────────────────────────
          +6 ┊ <smoldot::json_rpc::methods::AccountId as serde::de::Deserialize>::deserialize::h10e506bd54f2bc1f
          +6 ┊ Σ [1 Total Rows]

[arrudagates]

Thanks! Could you add an entry in bin/wasm-node/CHANGELOG.md as well?

Done!