Bump org.jetbrains.kotlin.android from 2.0.20 to 2.0.21

Bumps org.jetbrains.kotlin.android from 2.0.20 to 2.0.21.

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

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

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -9,7 +9,7 @@ constraintlayout = "2.1.4"
 desugar_jdk_libs = "2.1.2"
 documentfile = "1.0.1"
 junitJupiter = "5.11.2"
-kotlin = "2.0.20"
+kotlin = "2.0.21"
 lifecycleViewmodelKtx = "2.8.6"
 mapsforge = "0.21.0"
 material = "1.12.0"