fix: Exclude emotion's css prop from exported typedefs (#468)

Author: frankieyan

tsconfig.dist.json

@@ -4,5 +4,11 @@
         "rootDir": "./src",
         "declarationDir": "lib"
     },
-    "exclude": ["node_modules", "**/__mocks__", "**/__tests__"]
+    "exclude": [
+        "node_modules",
+        "**/__mocks__",
+        "**/__tests__",
+        "**/storybook-helper.*",
+        "**/*.stories.*"
+    ]
 }