[SPARK-48568][SQL] Improve Performance of CodeFormatter

[anton-erofeev]

What changes were proposed in this pull request?

Replace scala StringBuilder with java StringBuilder

Why are the changes needed?

https://issues.apache.org/jira/browse/SPARK-48568

Does this PR introduce any user-facing change?

No

How was this patch tested?

Pass github actions

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

No

[HyukjinKwon]

Can we have a micro benchmark?

[LuciferYang]

Can we have a micro benchmark?

+1 for micro benchmark. StringBuilder wraps j.l.StringBuilder,

final class StringBuilder(val underlying: java.lang.StringBuilder) extends AbstractSeq[Char]
  with ReusableBuilder[Char, String]
  with IndexedSeq[Char]
  with IndexedSeqOps[Char, IndexedSeq, StringBuilder]
  with IterableFactoryDefaults[Char, IndexedSeq]
  with java.lang.CharSequence
  with Serializable 

the functions should all directly operate on the underlying, so I'm not sure if this really brings a performance improvement. If it does, is this the only place worth change?