Bump kotlin_version from 1.8.22 to 1.9.0 (#489)

Bumps `kotlin_version` from 1.8.22 to 1.9.0.

Updates `org.jetbrains.kotlin:kotlin-gradle-plugin` from 1.8.22 to 1.9.0
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.8.22...v1.9.0)

Updates `org.jetbrains.kotlin:kotlin-stdlib` from 1.8.22 to 1.9.0
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.8.22...v1.9.0)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-gradle-plugin
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.jetbrains.kotlin:kotlin-stdlib
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: ligi <[email protected]>

build.gradle

@@ -1,6 +1,6 @@
 buildscript {
     ext {
-        kotlin_version = '1.8.22'
+        kotlin_version = '1.9.0'
 	// wait for upstream https://github.com/mockito/mockito/issues/2007
         mockito_version = '3.4.6'
         threetenbp_version = '1.6.8'