Rollup merge of rust-lang#75081 - jyn514:fix-logging, r=Mark-Simulacrum

Fix logging for rustdoc

rust-lang#74726 (comment)

Author: Manishearth

src/librustdoc/lib.rs

@@ -43,7 +43,7 @@ extern crate rustc_trait_selection;
 extern crate rustc_typeck;
 extern crate test as testing;
 #[macro_use]
-extern crate log;
+extern crate tracing as log;
 
 use std::default::Default;
 use std::env;