[Docs]: Remove unrequired commented out 2.7 content from release notes

QE: This JIRA is an internal doc enhancement relating to hidden content. No QE testing is required here.

The Fireball 2.13 release notes contain sections of 2.7 content that was commented out with //// during the early phases in case needed of this section:

3. New features, enhancements, and technical changes

The items that are required have been scoped in fireball tasks. The remaining content contains information that is outside the scope of current product guides and customers are referred to the quarkusio docs for detailed how-to information.

This task includes the clean-up of the release notes asciidoc, to remove the unrequired hidden content.