[DevOps Adoption] should be available for Ultimate tier only

Summary

The DevOps Adoption features, which exist at both the instance and group levels, are intended to be Ultimate features (according to epic and documentation). This moves them out of the Starter list and into the Ultimate list.

This was prompted by @pshutsin's observation in #326008 (comment 557625793).

Affected versions

13.6 to [13.12](!60032 (merged)].

Note: Feature flag defaulted to "off" during this period. It was enabled in %13.12 after the tiering was fixed.

Proposal

change the feature to be available for Ultimate tier only.

/cc @ljlane