Display additional minutes in group admin

What does this MR do?

Display additional minutes in group admin.

Closes #285517 (closed)

Screenshots (strongly suggested)

Second row is the addition:

This matches the minutes on the usage quotas page for the group:

and the customers' account in CustomersDot:

Does this MR meet the acceptance criteria?

Conformity

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• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
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