JPS, tests: Add docs for incremental/cacheVersionChanged tests

jps-plugin/jps-tests/test/org/jetbrains/kotlin/jps/build/AbstractDataContainerVersionChangedTest.kt

@@ -19,6 +19,9 @@ package org.jetbrains.kotlin.jps.build
 import org.jetbrains.kotlin.incremental.testingUtils.BuildLogFinder
 import org.jetbrains.kotlin.jps.targets.KotlinModuleBuildTarget
 
+/**
+ * @see [jps-plugin/testData/incremental/cacheVersionChanged/README.md]
+ */
 abstract class AbstractDataContainerVersionChangedTest : AbstractIncrementalCacheVersionChangedTest() {
     override val buildLogFinder: BuildLogFinder
         get() = BuildLogFinder(isDataContainerBuildLogEnabled = true)

jps-plugin/jps-tests/test/org/jetbrains/kotlin/jps/build/AbstractIncrementalCacheVersionChangedTest.kt

@@ -21,6 +21,9 @@ import org.jetbrains.kotlin.incremental.testingUtils.ModifyContent
 import org.jetbrains.kotlin.jps.incremental.CacheVersionManager
 import org.jetbrains.kotlin.jps.targets.KotlinModuleBuildTarget
 
+/**
+ * @see [jps-plugin/testData/incremental/cacheVersionChanged/README.md]
+ */
 abstract class AbstractIncrementalCacheVersionChangedTest : AbstractIncrementalJpsTest(allowNoFilesWithSuffixInTestData = true) {
     override fun performAdditionalModifications(modifications: List<Modification>) {
         val modifiedFiles = modifications.filterIsInstance<ModifyContent>().map { it.path }