Bump react/jsx-no-undef (undefined require) from warning to error

Reviewed By: weicool

Differential Revision: D5843154

fbshipit-source-id: 0729cb19e3b3664a235320e908af51b2f56cc4ae

.eslintrc

@@ -232,7 +232,7 @@
     "react/jsx-boolean-value": 0,
     "react/jsx-no-comment-textnodes": 1,
     "react/jsx-no-duplicate-props": 2,
-    "react/jsx-no-undef": 1,
+    "react/jsx-no-undef": 2,
     "react/jsx-sort-props": 0,
     "react/jsx-uses-react": 1,
     "react/jsx-uses-vars": 1,