Auto merge of #12243 - TravisDean:else-brace-check, r=ConnorGBrewster

Add style check and test for else braces

<!-- Please describe your changes on the following line: -->
Added a regex check to enforce project style guidelines. Added unit check. Catches:
```
}
else {
```
when it should be
`} else {`

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [ ] `./mach build -d` does not report any errors (no core files changed)
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12234 (github issue number if applicable).

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

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components/gfx/paint_context.rs

@@ -1788,8 +1788,11 @@ impl ScaledFontExtensionMethods for ScaledFont {
         let mut options = struct__AzDrawOptions {
             mAlpha: 1f64 as AzFloat,
             mCompositionOp: CompositionOp::Over as u8,
-            mAntialiasMode: if antialias { AntialiasMode::Subpixel as u8 }
-                            else { AntialiasMode::None as u8 }
+            mAntialiasMode: if antialias {
+                                AntialiasMode::Subpixel as u8
+                            } else {
+                                AntialiasMode::None as u8
+                            }
         };
 
         let mut origin = baseline_origin.clone();