group by not working as expected - returns varying results with each query run

Customer reported issue when running a specific query and it was returning different results sets. Supported was able to reproduce the issue on 1.2.5 2um 2pm root install system.

From customer issue:

When running a query with a group by outside of a temporary table that also used a group by, unexpected results are returned. It does not appear that the outside group by is working correctly and actually returns varying results with each run. The query is as follows:

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