Rollup merge of #106106 - jyn514:remote-tracking-branch, r=Mark-Simulacrum

Pass `branch.{branch}.remote=origin` to `git submodule update`

This works around a bug in git itself.
Fixes https://github.com/rust-lang/rust/issues/101144.

diff --cc src/bootstrap/lib.rs
index 3b9dba4109d3e6f1d2b8fe6c4aa047b204da4b5f,5cdd841cd6ed0b7d64993f57365a209ca142e8b7..3a0be7a85356f9ab1f89e083a6d989ea5cbd25dd
--- 1/src/bootstrap/lib.rs
--- 2/src/bootstrap/lib.rs
+++ b/src/bootstrap/lib.rs
@@@ -110,10 -110,9 +110,10 @@@ use std::fs::{self, File}
  use std::io;
  use std::io::ErrorKind;
  use std::path::{Path, PathBuf};
- use std::process::Command;
+ use std::process::{Command, Stdio};
  use std::str;
  
 +use build_helper::ci::CiEnv;
  use channel::GitInfo;
  use config::{DryRun, Target};
  use filetime::FileTime;