build(deps): bump kotlin from 2.0.20 to 2.0.21 (#19)

Bumps `kotlin` from 2.0.20 to 2.0.21.

Updates `org.jetbrains.kotlin.plugin.compose` from 2.0.20 to 2.0.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.0.21/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.20...v2.0.21)

Updates `org.jetbrains.kotlin.multiplatform` from 2.0.20 to 2.0.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.0.21/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.20...v2.0.21)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin.plugin.compose
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: org.jetbrains.kotlin.multiplatform
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -7,7 +7,7 @@ androidGradlePlugin = "8.7.0"
 androidx-activity-compose = "1.9.2"
 androidx-window = "1.3.0"
 compose-plugin = "1.7.0-rc01"
-kotlin = "2.0.20"
+kotlin = "2.0.21"
 
 [libraries]
 androidx-activity-compose = { module = "androidx.activity:activity-compose", version.ref = "androidx-activity-compose" }