Add a new host function for reporting fatal errors; make WASM backtraces readable when printing out errors (#10741)

* Add a new host function for reporting fatal errors

* Fix one of the wasmtime executor tests

* Have `#[runtime_interface(wasm_only)]` actually mean WASM-only, and not no_std-only

* Print out errors through `Display` instead of `Debug`

* Switch one more trait to require `Error` for its error instead of only `Debug`

* Align to review comments

substrate/utils/frame/rpc/system/src/lib.rs

@@ -106,7 +106,7 @@ where
 			let nonce = api.account_nonce(&at, account.clone()).map_err(|e| RpcError {
 				code: ErrorCode::ServerError(Error::RuntimeError.into()),
 				message: "Unable to query nonce.".into(),
-				data: Some(format!("{:?}", e).into()),
+				data: Some(e.to_string().into()),
 			})?;
 
 			Ok(adjust_nonce(&*self.pool, account, nonce))
@@ -141,7 +141,7 @@ where
 			let result = api.apply_extrinsic(&at, uxt).map_err(|e| RpcError {
 				code: ErrorCode::ServerError(Error::RuntimeError.into()),
 				message: "Unable to dry run extrinsic.".into(),
-				data: Some(format!("{:?}", e).into()),
+				data: Some(e.to_string().into()),
 			})?;
 
 			Ok(Encode::encode(&result).into())