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, 1 insertions, 4 deletions

diff --git a/library/std/src/io/impls.rs b/library/std/src/io/impls.rs
index a8a2e9413e1..85023540a81 100644
--- a/library/std/src/io/impls.rs
+++ b/library/std/src/io/impls.rs
@@ -2,12 +2,9 @@
 mod tests;
 
 use crate::alloc::Allocator;
-use crate::cmp;
 use crate::collections::VecDeque;
-use crate::fmt;
 use crate::io::{self, BorrowedCursor, BufRead, IoSlice, IoSliceMut, Read, Seek, SeekFrom, Write};
-use crate::mem;
-use crate::str;
+use crate::{cmp, fmt, mem, str};
 
 // =============================================================================
 // Forwarding implementations