Bump kotlin_version from 2.1.10 to 2.1.20

Bumps `kotlin_version` from 2.1.10 to 2.1.20.

Updates `org.jetbrains.kotlin:kotlin-gradle-plugin` from 2.1.10 to 2.1.20
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.10...v2.1.20)

Updates `org.jetbrains.kotlin:kotlin-stdlib` from 2.1.10 to 2.1.20
- [Release notes](https://github.com/JetBrains/kotlin/releases)
- [Changelog](https://github.com/JetBrains/kotlin/blob/master/ChangeLog.md)
- [Commits](JetBrains/kotlin@v2.1.10...v2.1.20)

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

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

Author: dependabot[bot]

build.gradle

@@ -1,5 +1,5 @@
 buildscript {
-    ext.kotlin_version = '2.1.10'
+    ext.kotlin_version = '2.1.20'
     repositories {
         google()
         mavenCentral()