Update `.rustfmt.toml`

Signed-off-by: Yuki Kishimoto <yukikishimoto@protonmail.com>

.rustfmt.toml

@@ -1,5 +1,9 @@
-group_imports = "StdExternalCrate"
-wrap_comments = true
-format_code_in_doc_comments = true
+tab_spaces = 4
+newline_style = "Auto"
+reorder_imports = true
+reorder_modules = true
+reorder_impl_items = false
+indent_style = "Block"
+normalize_comments = false
 imports_granularity = "Module"
-edition = "2021"
+group_imports = "StdExternalCrate"