Revert font stack changes (#1592)

* Revert `$body-font` changes

* Create thirty-pants-relate.md

Author: simurai

.changeset/thirty-pants-relate.md

@@ -0,0 +1,5 @@
+---
+"@primer/css": minor
+---
+
+Revert font stack changes

src/support/variables/typography.scss

@@ -32,28 +32,7 @@ $lh-condensed: 1.25 !default;
 $lh-default: 1.5 !default;
 
 // Font stacks
-$body-font:
-  // Apple OSs
-  -apple-system,
-  BlinkMacSystemFont,
-
-  // Windows
-  // Note this should be prioritized over `system-ui` to avoid legacy fonts.
-  // See https://infinnie.github.io/blog/2017/systemui.html
-  "Segoe UI Variable Text",
-  "Segoe UI",
-  "Meiryo", // Improves font rendering for Japanese, see https://github.com/primer/css/pull/1573.
-
-  // Linux-friendly system-level fonts + fallbacks
-  system-ui,
-  ui-sans-serif,
-  Helvetica,
-  Arial,
-  sans-serif,
-
-  // Emojis
-  "Apple Color Emoji",
-  "Segoe UI Emoji" !default;
+$body-font: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji" !default;
 
 // Monospace font stack
 // Note: SFMono-Regular needs to come before SF Mono to fix an older version of the font in Chrome