docs: add StackQL Provider Registry to showcase (#7760)

* Added StackQL Provider Registry doc site

* added StackQL Provider Registry image

* fixes

Co-authored-by: Joshua Chen <[email protected]>

Author: jeffreyaven

website/src/data/showcase/registry.stackql.io.png

@@ -2056,6 +2056,15 @@ const Users: User[] = [
     source: null,
     tags: ['product'],
   },
+  {
+    title: 'StackQL Provider Registry',
+    description:
+      'Cloud infra and SaaS provider documentation for StackQL providers.',
+    preview: require('./showcase/registry.stackql.io.png'),
+    website: 'https://registry.stackql.io/',
+    source: 'https://github.com/stackql/registry.stackql.io',
+    tags: ['opensource', 'product', 'large'],
+  },
   {
     title: 'Stryker Mutator',
     description: 'Mutation testing for JavaScript, .NET and JVM',