Implement associate compilations, KT-34009

Partial implementation of the associate compilations proposal. A
compilation can now contain links to other compilation that it compiles
against. This links will replace ad-hoc inter-compilation dependencies.

Issue #KT-34009 Fixed

libraries/tools/kotlin-gradle-plugin-api/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinCompilation.kt

@@ -67,6 +67,10 @@ interface KotlinCompilation<out T : KotlinCommonOptions> : Named, HasAttributes,
 
     fun source(sourceSet: KotlinSourceSet)
 
+    fun associateWith(other: KotlinCompilation<*>)
+
+    val associateWith: Set<KotlinCompilation<*>>
+
     override fun getName(): String = compilationName
 
     override val relatedConfigurationNames: List<String>