build: Bump the kotlin group with 5 updates

Bumps the kotlin group with 5 updates:

| Package | From | To |
| --- | --- | --- |
| [org.jetbrains.kotlin:kotlin-gradle-plugin](https://github.com/JetBrains/kotlin) | `2.1.20` | `2.1.21` |
| [org.jetbrains.kotlin.android](https://github.com/JetBrains/kotlin) | `2.1.20` | `2.1.21` |
| [org.jetbrains.kotlin.plugin.compose](https://github.com/JetBrains/kotlin) | `2.1.20` | `2.1.21` |
| [org.jetbrains.kotlin.jvm](https://github.com/JetBrains/kotlin) | `2.1.20` | `2.1.21` |
| [com.google.devtools.ksp](https://github.com/google/ksp) | `2.1.20-2.0.1` | `2.1.21-2.0.1` |


Updates `org.jetbrains.kotlin:kotlin-gradle-plugin` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin.android` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin.plugin.compose` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin.jvm` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin.android` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin.plugin.compose` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `org.jetbrains.kotlin.jvm` from 2.1.20 to 2.1.21
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.20...v2.1.21)

Updates `com.google.devtools.ksp` from 2.1.20-2.0.1 to 2.1.21-2.0.1
- [Release notes](https://github.com/google/ksp/releases)
- [Commits](google/ksp@2.1.20-2.0.1...2.1.21-2.0.1)

---
updated-dependencies:
- dependency-name: org.jetbrains.kotlin:kotlin-gradle-plugin
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: org.jetbrains.kotlin.android
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: org.jetbrains.kotlin.plugin.compose
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: org.jetbrains.kotlin.jvm
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: org.jetbrains.kotlin.android
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: org.jetbrains.kotlin.plugin.compose
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: org.jetbrains.kotlin.jvm
  dependency-version: 2.1.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
- dependency-name: com.google.devtools.ksp
  dependency-version: 2.1.21-2.0.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: kotlin
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -1,6 +1,6 @@
 [versions]
-kotlin = "2.1.20"
-ksp = "2.1.20-2.0.1"
+kotlin = "2.1.21"
+ksp = "2.1.21-2.0.1"
 agp = "8.10.0"
 hilt = "2.56.2"
 compose-bom = "2025.05.00"