embed distance oracle in duniter with subcommand

closes #140 (closed)

node/src/command.rs

@@ -306,7 +306,7 @@ pub fn run() -> sc_cli::Result<()> {
         }
         #[cfg(feature = "distance-oracle")]
         Some(Subcommand::DistanceOracle(cmd)) => {
-            sc_cli::build_runtime().unwrap().block_on(async move {
+            sc_cli::build_runtime()?.block_on(async move {
                 distance_oracle::run_and_save(
                     &distance_oracle::api::client(cmd.rpc_url.clone()).await,
                     distance_oracle::Settings {