Use concat! to break up a long string literal

crates/compiler/load_internal/src/file.rs

@@ -1899,7 +1899,11 @@ fn load_multi_threaded<'a>(
             // .print_to_stdout(Duration::default()); // TODO determine total elapsed time and use it here
 
             Err(LoadingProblem::FormattedReport(
-                "\n\nThere was an unrecoverable error in the Roc compiler. Try using the `roc check` command; that may give a more helpful error report.\n\n".to_string(),
+                concat!(
+                    "\n\nThere was an unrecoverable error in the Roc compiler. The `roc check` ",
+                    "command can sometimes give a more helpful error report than other commands.\n\n"
+                )
+                .to_string(),
             ))
         })
     }