[Build] Update kotlinApiVersionForProjectsUsedInIntelliJKotlinPlugin

The Kotlin compiler in monorepo was updated to `2.1.0` (IJPL-173508).

^KT-74254

Author: bnorm

gradle.properties

@@ -35,7 +35,7 @@ kotlinLanguageVersion=2.1
 
 # Should be less or equal to the Kotlin stdlib version used inside IntelliJ IDEA repository, see KT-62510.
 # IntelliJ IDEA Kotlin stdlib version can be found at https://github.com/JetBrains/intellij-community/blob/master/.idea/libraries/kotlin_stdlib.xml
-kotlinApiVersionForProjectsUsedInIntelliJKotlinPlugin=2.0
+kotlinApiVersionForProjectsUsedInIntelliJKotlinPlugin=2.1
 
 kotlin.build.gradlePlugin.version=0.0.40