ListItem JSX tag is not closed when used in SectionList

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When copy pasting the SectionList, got an error with a non closing JSX tag
What existing problem does the pull request solve?
Closing the JSX tag in 2 files
no test required
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Closes facebook#13525

Differential Revision: D4908495

Pulled By: javache

fbshipit-source-id: f2dc49c9238d1da8906f7daf144429a57ad725a3

Libraries/Lists/SectionList.js

@@ -191,7 +191,7 @@ type DefaultProps = typeof defaultProps;
  * Simple Examples:
  *
  *     <SectionList
- *       renderItem={({item}) => <ListItem title={item.title}}
+ *       renderItem={({item}) => <ListItem title={item.title} />}
  *       renderSectionHeader={({section}) => <H1 title={section.key} />}
  *       sections={[ // homogenous rendering between sections
  *         {data: [...], key: ...},

blog/2017-03-13-better-list-views.md

@@ -27,7 +27,7 @@ If you want to render a set of data broken into logical sections, maybe with sec
 
 ```
 <SectionList
-  renderItem={({item}) => <ListItem title={item.title}}
+  renderItem={({item}) => <ListItem title={item.title} />}
   renderSectionHeader={({section}) => <H1 title={section.key} />}
   sections={[ // homogenous rendering between sections
     {data: [...], key: ...},