[SPARK-51977] Improve SparkSQLRepl to support multiple lines

[dongjoon-hyun]

What changes were proposed in this pull request?

This PR aims to improve SparkSQLRepl example to support multiple lines.

Why are the changes needed?

To help users to check complex queries easily. As an example, SQL Pipe Syntax is added to the README.md.

FROM ORC.`/opt/spark/examples/src/main/resources/users.orc`
|> AGGREGATE COUNT(*) cnt
   GROUP BY name
|> ORDER BY cnt DESC, name ASC
;

Does this PR introduce any user-facing change?

No.

How was this patch tested?

After passing the CIs, do manual check.

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

No.

[dongjoon-hyun]

Thank you, @viirya . Merged to main.