Upgrade styled-jsx (#5953)

The latest version includes a fix to resolve conflicts with other libraries that use the `css` prop. Details https://github.com/zeit/styled-jsx/releases/tag/v3.1.3

packages/next/package.json

@@ -79,7 +79,7 @@
     "recursive-copy": "2.0.6",
     "resolve": "1.5.0",
     "strip-ansi": "3.0.1",
-    "styled-jsx": "3.1.1",
+    "styled-jsx": "3.1.3",
     "terser-webpack-plugin": "1.1.0",
     "tty-aware-progress": "1.0.3",
     "unfetch": "3.0.0",