[SPARK-53990] Use Java (Map|Set).of instead of Collections.(empty|singleton)(Map|Set)

[dongjoon-hyun]

What changes were proposed in this pull request?

This PR aims to use Java 9+ Map.of and Set.of APIs instead of the following.

• Collections.emptySet
• Collections.emptyMap
• Collections.singletonMap
• Collections.singletonSet

Why are the changes needed?

New Java APIs are concise and more intuitive.

- return Collections.emptyMap();
+ return Map.of();

- Collections.singletonMap(getCurrentStateId() + 1, state),
+ Map.of(getCurrentStateId() + 1, state),

In addition, this is aligned with

• [SPARK-53217][CORE][DSTREAM] Use Java Set.of instead of Sets.newHashSet spark#51942
• [SPARK-53235][CORE][TESTS] Use Java Set.of instead of ImmutableSet.of spark#51961
• [SPARK-53229][CORE][SQL][EXAMPLES][TESTS] Use Java Map.of instead of ImmutableMap.of spark#51954

Does this PR introduce any user-facing change?

No.

How was this patch tested?

Pass the CIs.

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

No.

[dongjoon-hyun]

All tests passed. Let me merge this since this is a straight-forward replacement.