Draft: Create commerce integrations group in Stages.yml

Why is this change being made?

As part of the ramping up of the Commerce Integrations team we're starting to assign tickets to ~"group::commerce integrations" for planning and organizational purposes. However as was pointed out in https://gitlab.com/gitlab-org/customers-gitlab-com/-/merge_requests/5464#note_1106668836 the data changes needed to support triage and other automation does not yet exist. This MR adds the needed group meta information to support existing tooling understanding the new group.

The Triage-Ops companion issue to this can be found at:

gitlab-org/quality/triage-ops#1131 (closed)

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