Add Web Performance Metrics (#1612)

readme.md

@@ -246,6 +246,7 @@
 - [Mobile Web Development](https://github.com/myshov/awesome-mobile-web-development#readme) - Creating a great mobile web experience.
 - [Storybook](https://github.com/lauthieb/awesome-storybook#readme) - Development environment for UI components.
 - [Blazor](https://github.com/AdrienTorris/awesome-blazor#readme) - .NET web framework using C#/Razor and HTML that runs in the browser with WebAssembly.
+- [Web Performance Metrics](https://github.com/csabapalfi/awesome-web-performance-metrics#readme) - Metrics to help understand page speed and user experience.
 
 
 ## Back-End Development