opt: add unique and distinct column to outside-histogram test

This commit adds a column `u` with a unique index, and a column `d`
with a non-unique index to the outside-histogram test table. Both
columns use the same histogram as the primary key `k` (and therefore
have no duplicate values).

This commit also adds tests that are similar to `Q1`, but using the
new columns instead of `k`. This shows the optimizer's behavior when
the "good" plan requires an index join, and when filtering on `d`,
shows how the optimizer behaves when no plan limits the max cardinality
of the query.

Epic: None

Release note: None

Author: DrewKimball