docs: update React Native version to 0.79 in getting started guide (#2751)

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## Summary:

updates the version in the getting started guide to 0.79

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problem does the pull request solve? -->

## Test Plan:

visit the docs page to see the updated page

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Author: dannyhw

docsite/docs/getting-started.md

@@ -13,10 +13,10 @@ For information around how to set up:
 
 ## Install React Native for macOS
 
-Remember to call `@react-native-community/cli init` from the place you want your project directory to live. Be sure to use the same minor version between React Native and React Native macOS. We'll use `^0.78.0`
+Remember to call `@react-native-community/cli init` from the place you want your project directory to live. Be sure to use the same minor version between React Native and React Native macOS. We'll use `^0.79.0`
 
 ```
-npx @react-native-community/cli init <projectName> --version 0.78
+npx @react-native-community/cli init <projectName> --version 0.79
 ```
 
 ### Navigate into this newly created directory