[react] add vietnamese

Author: m-inh

react/README.md

@@ -693,5 +693,6 @@ This style guide is mostly based on the standards that are currently prevalent i
   - ![th](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Thailand.png) **Thai**: [lvarayut/javascript-style-guide](https://github.com/lvarayut/javascript-style-guide/tree/master/react)
   - ![tr](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Turkey.png) **Turkish**: [alioguzhan/react-style-guide](https://github.com/alioguzhan/react-style-guide)
   - ![ua](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Ukraine.png) **Ukrainian**: [ivanzusko/javascript](https://github.com/ivanzusko/javascript/tree/master/react)
+  - ![vn](https://raw.githubusercontent.com/gosquared/flags/master/flags/flags/shiny/24/Vietnam.png) **Vietnam**: [uetcodecamp/jsx-style-guide](https://github.com/UETCodeCamp/jsx-style-guide)
 
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