[jb] clarify to install release not EAP gateway

Author: akosyakov

components/ide/jetbrains/gateway-plugin/doc/installing.md

@@ -1,5 +1,6 @@
 ## Installing Gitpod plugin in JetBrains Gateway
 
-- Install latest [JetBrains Gateway](https://www.jetbrains.com/remote-development/gateway/)
+- Install latest [JetBrains Gateway](https://www.jetbrains.com/help/idea/remote-development-a.html#gateway)
+  - Please make sure to install Release, not EAP version.
 - Launch Gateway and open plugin settings
 - Search for "Gitpod Gateway" and click install