Update the prerequisite section to include Frequency Access Testnet f… (#736)

Include the Frequency Access Testnet Account Setup form as a
prerequisite step in the SSO tutorial. Improve clarity, scan-ability,
and structure of the prerequisite section.

If the changes deviate too far from the rest of the docs, I'm happy to
roll it back to the list that was there before.

Closes #735

Author: emresurmeli

docs/src/GettingStarted/SSO.md

@@ -19,12 +19,24 @@ Resources:
 In this tutorial, you will set up a Sign In With Frequency button for use with Testnet, which will enable you to acquire onboarded, authenticated users with minimal steps.
 
 ## Prerequisites
-Ensure you have:
-- Registered your application as a [Provider on Frequency Testnet](./BecomeProvider.md).
-- A backend-only-accessible [running instance](../Run/GatewayServices/RunGatewayServices.md) of the Account Service.
-- Access to a Frequency RPC Node.
-    - Public Testnet Node: `wss://0.rpc.testnet.amplica.io`
 
+Before proceeding, ensure you have completed the following steps:
+
+✅ **Registered as a Provider**  
+Register your application as a [Provider on Frequency Testnet](./BecomeProvider.md).
+
+✅ **Completed the Access Form**  
+Fill out the [Frequency Access Testnet Account Setup form](https://docs.google.com/forms/d/e/1FAIpQLScN_aNMZpYqEdchSHrAR6MhKrVI1pA3SP6wxolAQCFckYoPOA/viewform).
+
+✅ **Set Up a Backend Instance**  
+You need a **backend-only-accessible** [running instance](../Run/GatewayServices/RunGatewayServices.md) of the Account Service.
+
+✅ **Access to a Frequency RPC Node**  
+- **Public Testnet Node:**  
+  ```plaintext
+  wss://0.rpc.testnet.amplica.io
+  ```
+  
 ## Overview
 
 1. Application creates a signed request SIWF URL that contains a callback URL.