Reformat use declarations.

The previous commit updated `rustfmt.toml` appropriately. This commit is
the outcome of running `x fmt --all` with the new formatting options.

compiler/rustc_builtin_macros/src/compile_error.rs

@@ -1,10 +1,11 @@
 // The compiler code necessary to support the compile_error! extension.
 
-use crate::util::get_single_str_from_tts;
 use rustc_ast::tokenstream::TokenStream;
 use rustc_expand::base::{DummyResult, ExpandResult, ExtCtxt, MacroExpanderResult};
 use rustc_span::Span;
 
+use crate::util::get_single_str_from_tts;
+
 pub(crate) fn expand_compile_error<'cx>(
     cx: &'cx mut ExtCtxt<'_>,
     sp: Span,