Remove version field from struct returned by rpc_methods

[tomaka]

Mimics the change done here: paritytech/substrate#12261

Let's merge this PR only if paritytech/substrate#12261 is approved and merged.

[mergify]

Automatically approving tomaka's pull requests. This auto-approval will be removed once more maintainers are active.

[github-actions]

twiggy diff report

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

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 Delta Bytes │ Item
─────────────┼─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
        -318 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h3ee3b8bb3a29c778
        +314 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h79e45a3d6b68e607
        -257 ┊ <smoldot::json_rpc::methods::RpcMethods as serde::ser::Serialize>::serialize::_::<impl serde::ser::Serialize for <smoldot::json_rpc::methods::RpcMethods as serde::ser::Serialize>::serialize::SerdeRpcMethods>::serialize::hdff94f68de5b8826
        +233 ┊ <smoldot::json_rpc::methods::RpcMethods as serde::ser::Serialize>::serialize::_::<impl serde::ser::Serialize for <smoldot::json_rpc::methods::RpcMethods as serde::ser::Serialize>::serialize::SerdeRpcMethods>::serialize::h11e3c7c7f4a5459e
         -84 ┊ <smoldot::json_rpc::methods::RpcMethods as serde::ser::Serialize>::serialize::h735630db00d52a9e
         +71 ┊ <smoldot::json_rpc::methods::RpcMethods as serde::ser::Serialize>::serialize::h48184d7a3755726a
         -38 ┊ core::ptr::drop_in_place<core::future::from_generator::GenFuture<smoldot_light::json_rpc_service::getters::<impl smoldot_light::json_rpc_service::Background<smoldot_light_wasm::platform::Platform>>::rpc_methods::{{closure}}>>::h9962a96bcad90d41
         +38 ┊ core::ptr::drop_in_place<core::future::from_generator::GenFuture<smoldot_light::json_rpc_service::getters::<impl smoldot_light::json_rpc_service::Background<smoldot_light_wasm::platform::Platform>>::rpc_methods::{{closure}}>>::hc9d2bdee2f806812
          -3 ┊ smoldot::json_rpc::methods::Response::to_json_response::h02347c389273d279
         -44 ┊ Σ [9 Total Rows]