Fix docs instead

Author: hasparus

packages/docs/src/pages/readme.mdx

@@ -2,6 +2,6 @@
 title: 'Readme'
 ---
 
-import Readme from 'theme-ui/README.md'
+import Readme from '../../../theme-ui/README.md'
 
 <Readme />

packages/theme-ui/package.json

@@ -33,8 +33,7 @@
       },
       "default": "./jsx-dev-runtime/dist/theme-ui-jsx-dev-runtime.cjs.js"
     },
-    "./package.json": "./package.json",
-    "./README.md": "./README.md"
+    "./package.json": "./package.json"
   },
   "types": "dist/theme-ui.cjs.d.ts",
   "sideEffects": false,