add link to js

Author: Michelle Zhang

docs/product/explore/feature-flags/index.mdx

@@ -29,7 +29,7 @@ In order to take advantage of the full feature flag experience available, there
 In order to gain access to **feature flag evaluation tracking**, you need to set up your SDK to include Sentry's feature flag integration.
 
 Learn more about the languages we currently support and how to set up the SDK:
-* JavaScript
+* [JavaScript](/platforms/javascript/feature-flags/)
 * [Python](/platforms/python/feature-flags/)
 
 ## Set Up Your Integration-Specific Webhook