Bump org.jetbrains.kotlin:kotlin-gradle-plugin in /android

Bumps [org.jetbrains.kotlin:kotlin-gradle-plugin](https://github.com/JetBrains/kotlin) from 2.0.0 to 2.0.20.
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/v2.0.20/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.0.0...v2.0.20)

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

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

android/build.gradle

@@ -2,7 +2,7 @@ group = "dev.fluttercommunity.android_id"
 version = "1.0-SNAPSHOT"
 
 buildscript {
-    ext.kotlin_version = "2.0.0"
+    ext.kotlin_version = "2.0.20"
     repositories {
         google()
         mavenCentral()