DDS: Tenable.io README Update (#20866)

* add tenable.io account user role in README

* address GitHub review comment

Author: akaila-crest

tenable_io/README.md

@@ -15,7 +15,7 @@ This integration collects logs from the sources listed above and sends them to D
 
 ### Generate API credentials in Tenable.io
 
-1. Log in to your [Tenable.io][4] account.
+1. Log in to [Tenable.io][4] with an account that has the `Administrator` user role.
 2. Click the profile icon and select **My Profile**.
 3. Navigate to the **API Keys** section.
 4. Click the **Generate** button in the lower right-corner of the page.