Updated broken link.

Summary:
The URL http://makeitopen.com/tutorials/building-the-f8-app/planning/ is 404. Updated with correct URL.

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Closes #16976

Differential Revision: D6472303

Pulled By: shergin

fbshipit-source-id: 65c829384b4c9c3468c1c73aa10c8e6aa0164d05

docs/more-resources.md

@@ -22,7 +22,7 @@ If you're looking for a library that does a specific thing, check out [Awesome R
 
 Try out apps from the [Showcase](https://facebook.github.io/react-native/showcase.html) to see what React Native is capable of! There are also some [example apps on GitHub](https://github.com/ReactNativeNews/React-Native-Apps). You can run the apps on a simulator or device, and you can see the source code for these apps, which is neat.
 
-The folks who built the app for Facebook's F8 conference in 2016 also [open-sourced the code](https://github.com/fbsamples/f8app) and wrote up a [detailed series of tutorials](http://makeitopen.com/tutorials/building-the-f8-app/planning/). This is useful if you want a more in-depth example that's more realistic than most sample apps out there.
+The folks who built the app for Facebook's F8 conference in 2016 also [open-sourced the code](https://github.com/fbsamples/f8app) and wrote up a [detailed series of tutorials](http://makeitopen.com/docs/en/1-1-planning.html). This is useful if you want a more in-depth example that's more realistic than most sample apps out there.
 
 ## Extending React Native