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/style/properties/shorthand/font.mako.rs

@@ -120,7 +120,7 @@
             return Err(input.new_custom_error(StyleParseErrorKind::UnspecifiedError))
         }
 
-        let family = FontFamily::parse(input)?;
+        let family = FontFamily::parse_specified(input)?;
         Ok(expanded! {
             % for name in "style weight stretch variant_caps".split():
                 font_${name}: unwrap_or_initial!(font_${name}, ${name}),