[SPARK-54007][CORE][SQL] Use Java Set.of instead of Collections.emptySet

[dongjoon-hyun]

What changes were proposed in this pull request?

This PR aims to use Java 9+ Set.of() API instead of Collections.emptySet() and add Scalastyle and Checkstyle rules.

Why are the changes needed?

Like TableCatalog.java example of this PR, we had better use Set simply and uniformly from Apache Spark 4.1.0.

- import java.util.Collections;
...
- default Set<TableCatalogCapability> capabilities() { return Collections.emptySet(); }
+ default Set<TableCatalogCapability> capabilities() { return Set.of(); }

Does this PR introduce any user-facing change?

No behavior change.

How was this patch tested?

Pass the CIs.

Was this patch authored or co-authored using generative AI tooling?

No.

[vrozov]

+1, LGTM.

[dongjoon-hyun]

Thank you, @vrozov .

[dongjoon-hyun]

Thank you, @HyukjinKwon . Merged to master for Apache Spark 4.1.0-preview3.