Auto merge of #125443 - nnethercote:rustfmt-use-decls, r=lcnr,cuviper,GuillaumeGomez

rustfmt `use` declarations

This PR implements https://github.com/rust-lang/compiler-team/issues/750, which changes how `use` declarations are formatted by adding these options to `rustfmt.toml`:
```
group_imports = "StdExternalCrate"
imports_granularity = "Module"
```

r? `@ghost`

1 files changed, 3 insertions, 5 deletions

diff --git a/library/alloc/src/alloc.rs b/library/alloc/src/alloc.rs
index f7d10339689..db2d752cfde 100644
--- a/library/alloc/src/alloc.rs
+++ b/library/alloc/src/alloc.rs
@@ -2,16 +2,14 @@
 
 #![stable(feature = "alloc_module", since = "1.28.0")]
 
+#[stable(feature = "alloc_module", since = "1.28.0")]
+#[doc(inline)]
+pub use core::alloc::*;
 #[cfg(not(test))]
 use core::hint;
-
 #[cfg(not(test))]
 use core::ptr::{self, NonNull};
 
-#[stable(feature = "alloc_module", since = "1.28.0")]
-#[doc(inline)]
-pub use core::alloc::*;
-
 #[cfg(test)]
 mod tests;