Update apiVersion/languageVersion to 1.9 for atomics implementation.

In order to use new native atomics from kotlin.concurrent package available since Kotlin 1.9, it is required to update apiVersion to 1.9. apiVersion of atomicfu-gradle-plugin is kept equal to 1.4 for compatibility.

Author: mvicsokolova

gradle/compile-options.gradle

@@ -18,8 +18,8 @@ ext.configureKotlin = { isMultiplatform ->
 
     kotlin.sourceSets.all {
         languageSettings {
-            apiVersion = KotlinAggregateBuild.getOverriddenKotlinApiVersion(project) ?: "1.4"
-            languageVersion = KotlinAggregateBuild.getOverriddenKotlinLanguageVersion(project) ?: "1.4"
+            apiVersion = KotlinAggregateBuild.getOverriddenKotlinApiVersion(project) ?: "1.9"
+            languageVersion = KotlinAggregateBuild.getOverriddenKotlinLanguageVersion(project) ?: "1.9"
             optIn('kotlinx.cinterop.ExperimentalForeignApi')
         }
     }