build(deps): bump kotlin from 1.9.20 to 1.9.21

Bumps `kotlin` from 1.9.20 to 1.9.21.

Updates `org.jetbrains.kotlin.android` from 1.9.20 to 1.9.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.20...v1.9.21)

Updates `org.jetbrains.kotlin.kapt` from 1.9.20 to 1.9.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v1.9.20...v1.9.21)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin.android
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.jetbrains.kotlin.kapt
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

gradle/libs.versions.toml

@@ -1,7 +1,7 @@
 [versions]
 android = "8.1.4"
 compose-compiler = "1.5.4"
-kotlin = "1.9.20"
+kotlin = "1.9.21"
 
 [plugins]
 android = { id = "com.android.library", version.ref = "android" }