Kotlin: Avoid "generic specialisation" label collisions

We had a global set of labels for generic specialisations that we'd
extracted, but these labels could contain references to other labels,
and thus you can get false collisions between labels for different TRAP
files. We now only keep the set for a single TRAP file, and live with
the extra TRAP duplication that we get from that.

java/kotlin-extractor/src/main/kotlin/KotlinExtractorExtension.kt

@@ -138,7 +138,6 @@ class KotlinExtractorExtension(
 }
 
 class KotlinExtractorGlobalState {
-    val genericSpecialisationsExtracted = HashSet<String>()
     // These three record mappings of classes, functions and fields that should be replaced wherever they are found.
     // As of now these are only used to fix IR generated by the Gradle Android Extensions plugin, hence e.g. IrProperty
     // doesn't have a map as that plugin doesn't generate them. If and when these are used more widely additional maps