chore(deps): update plugin org.jetbrains.kotlin.android to v2.4.0 (#412)

This PR contains the following updates:

| Package | Change | [Age](https://docs.renovatebot.com/merge-confidence/) | [Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| org.jetbrains.kotlin.android | `2.3.21` → `2.4.0` | ![age](https://developer.mend.io/api/mc/badges/age/maven/org.jetbrains.kotlin.android:org.jetbrains.kotlin.android.gradle.plugin/2.4.0?slim=true) | ![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.jetbrains.kotlin.android:org.jetbrains.kotlin.android.gradle.plugin/2.3.21/2.4.0?slim=true) |

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Reviewed-on: https://codeberg.org/guettli/sharedinbox/pulls/412

android/settings.gradle.kts

@@ -20,7 +20,7 @@ pluginManagement {
 plugins {
     id("dev.flutter.flutter-plugin-loader") version "1.0.0"
     id("com.android.application") version "8.13.2" apply false
-    id("org.jetbrains.kotlin.android") version "2.3.21" apply false
+    id("org.jetbrains.kotlin.android") version "2.4.0" apply false
 }
 
 include(":app")