Auto merge of #11329 - c-rhodes:11320, r=jdm

Report use statements that use {} with only one entry

Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
- [X ] `./mach build -d` does not report any errors
- [X ] `./mach test-tidy --faster` does not report any errors
- [X ] These changes fix #11320  (github issue number if applicable).

Either:
- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process.

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tests/unit/script/dom/blob.rs

@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use script::dom::blob::{DataSlice};
+use script::dom::blob::DataSlice;
 use std::sync::Arc;
 
 #[test]

tests/unit/style/attr.rs

@@ -4,7 +4,7 @@
 
 use app_units::Au;
 use style::attr::{AttrValue, parse_length};
-use util::str::{LengthOrPercentageOrAuto};
+use util::str::LengthOrPercentageOrAuto;
 
 #[test]
 fn test_parse_double() {