Provide a separate class for representing metadata version in kotlinx-metadata

Separate class allows encapsulating comparison, equality, and structure of version parts.
It also makes more sense from API standpoint than plain `IntArray`.

plugins/jvm-abi-gen/src/org/jetbrains/kotlin/jvm/abi/JvmAbiMetadataProcessor.kt

@@ -6,6 +6,7 @@
 package org.jetbrains.kotlin.jvm.abi
 
 import kotlinx.metadata.*
+import kotlinx.metadata.jvm.JvmMetadataVersion
 import kotlinx.metadata.jvm.KotlinClassMetadata
 import kotlinx.metadata.jvm.Metadata
 import kotlinx.metadata.jvm.localDelegatedProperties
@@ -46,7 +47,7 @@ fun abiMetadataProcessor(annotationVisitor: AnnotationVisitor): AnnotationVisito
             // TODO: maybe jvm-abi-gen should throw this exception by default, and not only in tests.
             if (System.getProperty("idea.is.unit.test").toBoolean()) {
                 val actual = "${metadataVersion[0]}.${metadataVersion[1]}"
-                val expected = KotlinClassMetadata.COMPATIBLE_METADATA_VERSION.let { "${it[0]}.${it[1]}" }
+                val expected = JvmMetadataVersion.CURRENT.toString()
                 throw AssertionError(
                     "jvm-abi-gen can't process class file with the new metadata version because the version of kotlinx-metadata-jvm " +
                             "it depends on is too old.\n" +