Switch kotlin version to 1.8

with appropriate fixes in testdata, tests and other
places.

core/compiler.common.jvm/src/org/jetbrains/kotlin/load/java/JavaNullabilityAnnotationSettings.kt

@@ -36,7 +36,7 @@ val NULLABILITY_ANNOTATION_SETTINGS: NullabilityAnnotationStates<JavaNullability
         FqName("lombok") to JavaNullabilityAnnotationsStatus.DEFAULT,
         JSPECIFY_ANNOTATIONS_PACKAGE to JavaNullabilityAnnotationsStatus(
             reportLevelBefore = ReportLevel.WARN,
-            sinceVersion = KotlinVersion(1, 8),
+            sinceVersion = KotlinVersion(1, 9),
             reportLevelAfter = ReportLevel.STRICT
         ),
         FqName("io.reactivex.rxjava3.annotations") to JavaNullabilityAnnotationsStatus(

core/metadata.jvm/src/org/jetbrains/kotlin/metadata/jvm/deserialization/JvmMetadataVersion.kt

@@ -26,7 +26,7 @@ class JvmMetadataVersion(versionArray: IntArray, val isStrictSemantics: Boolean)
 
     companion object {
         @JvmField
-        val INSTANCE = JvmMetadataVersion(1, 7, 1)
+        val INSTANCE = JvmMetadataVersion(1, 8, 0)
 
         @JvmField
         val INVALID_VERSION = JvmMetadataVersion()