Solving weird bug

In polkadot:

---- call_function_actually_work stdout ----
thread 'call_function_actually_work' panicked at 'called `Result::unwrap()` on an `Err` value: RpcTransactionError { code: -32700, message: "Parse error", data: None }', node/test/service/tests/call-function.rs:29:60

Issues related:

serde-rs/json#559
serde-rs/serde#773

client/rpc-api/Cargo.toml

@@ -16,7 +16,7 @@ targets = ["x86_64-unknown-linux-gnu"]
 codec = { package = "parity-scale-codec", version = "1.3.4" }
 derive_more = "0.99.2"
 futures = { version = "0.3.1", features = ["compat"] }
-jsonrpc-core = "15.1.0"
+jsonrpc-core = { version = "15.1.0", features = ["arbitrary_precision"] }
 jsonrpc-core-client = "15.1.0"
 jsonrpc-derive = "15.1.0"
 jsonrpc-pubsub = "15.1.0"