Auto merge of #19366 - CYBAI:font-family-out-of-mako, r=emilio

style: Move font-family outside of mako

This is a sub-PR of #19015
Besides, this is the last PR for `font.mako.rs`! 🎉
r? emilio

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #19355
- [x] These changes do not require tests

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components/script/dom/element.rs

@@ -587,9 +587,9 @@ impl LayoutElementHelpers for LayoutDom<Element> {
                 shared_lock,
                 PropertyDeclaration::FontFamily(
                     font_family::SpecifiedValue::Values(
-                        font_family::computed_value::FontFamilyList::new(vec![
-                            font_family::computed_value::FontFamily::from_atom(
-                                font_family)])))));
+                        computed::font::FontFamilyList::new(Box::new([
+                            computed::font::SingleFontFamily::from_atom(
+                                font_family)]))))));
         }
 
         let font_size = self.downcast::<HTMLFontElement>().and_then(|this| this.get_size());