[DF] Fix regressions in EliminateAggDistinct, run cargo test in CI

[andygrove]

We haven't been running cargo test in CI and some regressions crept in.

The goal of this PR is just to get us back to a stable point and enable Rust tests in CI.

Changes in this PR:

• Run cargo test in CI
• Revert to an earlier version of the EliminateAggDistinct rule and ignore 2 failing tests

Proof that this works (from the logs):

running 9 tests
test sql::optimizer::eliminate_agg_distinct::tests::test_count_and_distinct_no_group_by ... ok
test sql::optimizer::eliminate_agg_distinct::tests::test_count_and_distinct_no_group_by_with_alias ... ok
test sql::optimizer::eliminate_agg_distinct::tests::test_multiple_distinct ... ok
test sql::optimizer::eliminate_agg_distinct::tests::test_count_and_distinct_group_by ... ok
test sql::optimizer::eliminate_agg_distinct::tests::test_multiple_distinct_with_aliases ... ok
test sql::optimizer::eliminate_agg_distinct::tests::test_single_distinct_group_by ... ignored
test sql::optimizer::eliminate_agg_distinct::tests::test_single_distinct_group_by_with_alias ... ignored
test sql::optimizer::eliminate_agg_distinct::tests::test_single_distinct_no_group_by ... ok
test sql::optimizer::eliminate_agg_distinct::tests::test_single_distinct_no_group_by_with_alias ... ok

test result: ok. 7 passed; 0 failed; 2 ignored; 0 measured; 0 filtered out; finished in 0.01s

[codecov-commenter]

Codecov Report

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