[KYUUBI #6674] Bump Scalafmt to 3.9.x

# 🔍 Description
## Issue References 🔗

This pull request fixes #

## Describe Your Solution 🔧

Without this PR:
- use and conform Scalafmt 3.7.x
- forcing all the imports from the same parent package, which is even violation the max length of the line

With this PR:
- use and conform Scalafmt 3.9.x
- Scalafmt 3.8.2 changes the binpack style: https://github.com/scalameta/scalafmt/releases/tag/v3.8.2
- change to `binPack.importSelectors=singleLine`, minimizing the impacts to existed code

## Types of changes 🔖

- [ ] Bugfix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)

## Test Plan 🧪

#### Behavior Without This Pull Request ⚰️

#### Behavior With This Pull Request 🎉

#### Related Unit Tests

---

# Checklist 📝

- [ ] This patch was not authored or co-authored using [Generative Tooling](https://www.apache.org/legal/generative-tooling.html)

**Be nice. Be informative.**

Closes #6674 from bowenliang123/scalafmt38.

Closes #6674

d9f4f9d [Bowen Liang] 3.9.0
438a07d [Bowen Liang] reformat
2df5066 [liangbowen] bump scalafmt to 3.8

Lead-authored-by: Bowen Liang <[email protected]>
Co-authored-by: liangbowen <[email protected]>
Signed-off-by: Bowen Liang <[email protected]>

Author: bowenliang123

.scalafmt.conf

@@ -1,4 +1,4 @@
-version = 3.7.5
+version = 3.9.0
 runner.dialect=scala212
 project.git=true
 
@@ -11,7 +11,7 @@ assumeStandardLibraryStripMargin = true
 danglingParentheses.preset = false
 docstrings.style = Asterisk
 docstrings.wrap = no
-importSelectors = singleLine
+binPack.importSelectors = singleLine
 indent.extendSite = 2
 literals.hexDigits = Upper
 maxColumn = 100

kyuubi-util-scala/src/test/scala/org/apache/kyuubi/util/AssertionUtils.scala

@@ -76,9 +76,8 @@ object AssertionUtils {
       path: Path,
       expectedLines: Traversable[String],
       regenScript: String,
-      splitFirstExpectedLine: Boolean = false)(implicit
-      prettifier: Prettifier,
-      pos: Position): Unit = {
+      splitFirstExpectedLine: Boolean =
+        false)(implicit prettifier: Prettifier, pos: Position): Unit = {
     val fileSource = Source.fromFile(path.toUri, StandardCharsets.UTF_8.name())
     try {
       def expectedLinesIter = if (splitFirstExpectedLine) {

pom.xml

@@ -266,7 +266,7 @@
         <spotless.python.includes></spotless.python.includes>
         <spotless.python.black.version>22.3.0</spotless.python.black.version>
         <!-- Please also update .scalafmt.conf when you change it here -->
-        <spotless.scala.scalafmt.version>3.7.5</spotless.scala.scalafmt.version>
+        <spotless.scala.scalafmt.version>3.9.0</spotless.scala.scalafmt.version>
 
         <distMgmtReleaseId>apache.releases.https</distMgmtReleaseId>
         <distMgmtReleaseName>Apache Release Distribution Repository</distMgmtReleaseName>