Update formatting for support packages (#1189)

<!-- Explain the changes introduced in your PR -->

Update formatting to distinguish these as separate options

## Pull Request approval

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Author: gabtorre

docs/sla/index.mdx

@@ -107,7 +107,9 @@ Purchasing Premium Support provides several of the following services beyond tho
 - Heightened Support via Slack - Faster response times and closer collaboration through direct access to Sourcegraph experts with closer connection to end users and administrators.
 - More Proactive Collaboration - Hands-on technical guidance to ensure successful migrations, upgrades, and maintenance; early access to new features; quarterly insights reports.
 
-### Premium Support SLAs
+### Premium Support Packages
+
+### Package 1: Premium Support SLAs
 
 Premium Support SLAs give customers access to our Support team 24x7 for Severity 0 and 1 issues that critically impact your instance and ability to use Sourcegraph.
 
@@ -117,12 +119,12 @@ This service is provided for all GA products Sourcegraph offers, not for any [Ex
 
 >NOTE: This package includes access to Slack Support
 
-### Dedicated Support
+### Package 2: Dedicated Support
 
 Access to named senior support engineers who will have knowledge of your infrastructure and can help reduce the time needed to triage, diagnose, and resolve an issue in your instance.
 
 >NOTE: This package includes access to Slack Support
 
-### Slack Support
+### Package 3: Slack Support
 
 Slack Support provides access to creating tickets directly from Slack, allowing customers to resolve tickets directly from a familiar interface and allowing for greater collaboration between Support and customers.