Describe the problem
In support issue https://github.com/cockroachlabs/support/issues/1949, a hash group-by + TopK plan is chosen over a streaming group-by when there is a LIMIT on the query because of unique constraints on certain columns, causing the number of grouping columns to be reduced by the optimizer. When one of the unique indexes is dropped, the fast query plan is picked.

To Reproduce
Use the statement bundles in the support issue.

Jira issue: CRDB-22320