[SPARK-37538][SQL] Replace single projection expand

[tanelk]

What changes were proposed in this pull request?

In the Optimizer replace all instances of Expand with only 1 projection with a Project.

Why are the changes needed?

Both grouping sets and distinct aggregations can create Expand with only 1 projection. Removing those can improve the performance in two ways:

• Enable optimization rules, that can not work with Expand
• Avoid unnecessary copying - ExpandExec has needCopyResult: Boolean = true

Does this PR introduce any user-facing change?

No

How was this patch tested?

New UT

[SparkQA]

Kubernetes integration test starting
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/50382/

[SparkQA]

Kubernetes integration test status failure
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/50382/

[SparkQA]

Test build #145907 has finished for PR 34800 at commit 5567766.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[HyukjinKwon]

Maybe let's add a JIRA number as the prefix.

[SparkQA]

Kubernetes integration test starting
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/50471/

[SparkQA]

Kubernetes integration test status failure
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/50471/

[SparkQA]

Kubernetes integration test starting
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/50477/

[SparkQA]

Kubernetes integration test status failure
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/50477/

[SparkQA]

Test build #145995 has finished for PR 34800 at commit 0e166aa.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #146001 has finished for PR 34800 at commit fa36637.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[github-actions]

We're closing this PR because it hasn't been updated in a while. This isn't a judgement on the merit of the PR in any way. It's just a way of keeping the PR queue manageable.
If you'd like to revive this PR, please reopen it and ask a committer to remove the Stale tag!