Replace Spectrum links with GitHub Discussions (facebook#9102)

Author: iansu

README.md

@@ -7,7 +7,7 @@ Create React apps with no build configuration.
 
 Create React App works on macOS, Windows, and Linux.<br>
 If something doesn’t work, please [file an issue](https://github.com/facebook/create-react-app/issues/new).<br>
-If you have questions or need help, please ask in our [Spectrum](https://spectrum.chat/create-react-app) community.
+If you have questions or need help, please ask in [GitHub Discussions](https://github.com/facebook/create-react-app/discussions).
 
 ## Quick Overview
 

docusaurus/website/docusaurus.config.js

@@ -82,8 +82,8 @@ const siteConfig = {
                 'https://stackoverflow.com/questions/tagged/create-react-app',
             },
             {
-              label: 'Spectrum',
-              href: 'https://spectrum.chat/create-react-app',
+              label: 'GitHub Discussions',
+              href: 'https://github.com/facebook/create-react-app/discussions',
             },
             {
               label: 'Twitter',