Remove duplicated tracing span in bootstrap

Author: Kobzol

src/bootstrap/src/core/build_steps/compile.rs

@@ -2494,9 +2494,6 @@ pub fn stream_cargo(
 ) -> bool {
     let mut cmd = cargo.into_cmd();
 
-    #[cfg(feature = "tracing")]
-    let _run_span = crate::utils::tracing::trace_cmd(&cmd);
-
     // Instruct Cargo to give us json messages on stdout, critically leaving
     // stderr as piped so we can get those pretty colors.
     let mut message_format = if builder.config.json_output {