DOCS-1575 - Add Fed environment support note for scheduled reports

[JV0812]

Purpose of this pull request

Added a note to the scheduled reports documentation indicating that scheduled reports are now supported in the Fed deployment environment.

Ticket (if applicable)

https://sumologic.atlassian.net/browse/DOCS-1575

Select the type of change

• Updating existing documentation

For new content

• I have reviewed the Sumo Logic Style Guide

Checklist

Please check off items as applicable:

• My doc follows the style guidelines
• I have performed a self-review of my own changes
• I have run Docusaurus locally to ensure the site builds successfully
• I have made corresponding changes to the documentation (if applicable)