[SPARK-33847][SQL][FOLLOWUP] Remove the CaseWhen should consider deterministic

[wangyum]

What changes were proposed in this pull request?

This pr fix remove the CaseWhen if elseValue is empty and other outputs are null because of we should consider deterministic.

Why are the changes needed?

Fix bug.

Does this PR introduce any user-facing change?

No.

How was this patch tested?

Unit test.

[wangyum]

cc @cloud-fan

[cloud-fan]

We need to fix https://github.com/apache/spark/pull/30852/files#diff-9723970916a34149cbb2e3a2853614e523a8a00d5a126926c54f23b4b758e3baR96 as well.

To simplify the code, I'd suggest we also turn unspecified else value into false in the rule ReplaceNullWithFalseInPredicate. It's idempotent and should not have a real perf impact even if there is no following optimizations.

[SparkQA]

Kubernetes integration test starting
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/38072/

[SparkQA]

Kubernetes integration test status success
URL: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder-K8s/38072/

[SparkQA]

Test build #133478 has finished for PR 30960 at commit 4c21e43.

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

[SparkQA]

Test build #133483 has finished for PR 30960 at commit 41a8fed.

• This patch fails SparkR unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[cloud-fan]

This is definitely not related to Spark R. Mering to master, thanks!