Auto merge of #21661 - chansuke:format_size_of_test, r=jdm

Format component size_of_test

<!-- Please describe your changes on the following line: -->
Format `components/size_of_test` by:
```
rustfmt components/size_of_test/*.rs
```
---
<!-- 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` does not report any errors
- [ ] These changes fix part of #21373.
- [x] These changes do not require tests because they format code only.

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components/size_of_test/lib.rs

@@ -13,16 +13,22 @@ macro_rules! size_of_test {
                 panic!(
                     "Your changes have decreased the stack size of {} from {} to {}. \
                      Good work! Please update the expected size in {}.",
-                    stringify!($t), old, new, file!()
+                    stringify!($t),
+                    old,
+                    new,
+                    file!()
                 )
             } else if new > old {
                 panic!(
                     "Your changes have increased the stack size of {} from {} to {}. \
                      Please consider choosing a design which avoids this increase. \
                      If you feel that the increase is necessary, update the size in {}.",
-                    stringify!($t), old, new, file!()
+                    stringify!($t),
+                    old,
+                    new,
+                    file!()
                 )
             }
         }
-    }
+    };
 }