Fixed typo in docs.

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Closes https://github.com/facebook/react-native/pull/11459

Differential Revision: D4339946

Pulled By: lacker

fbshipit-source-id: d95e7c62dbf7bf6fd2ab3739b3d64bfcbe83e24a

Libraries/ReactNative/AppRegistry.js

@@ -51,7 +51,7 @@ type AppConfig = {
  *
  * To "stop" an application when a view should be destroyed, call
  * `AppRegistry.unmountApplicationComponentAtRootTag` with the tag that was
- * pass into `runApplication`. These should always be used as a pair.
+ * passed into `runApplication`. These should always be used as a pair.
  *
  * `AppRegistry` should be `require`d early in the `require` sequence to make
  * sure the JS execution environment is setup before other modules are