Build: Fix unconditional adding kotlin-reflect.jar for JPS build

Should be added only when JPS build enabled to avoid kotlin-reflect
reindexing after each build

compiler/tests-java8/build.gradle.kts

@@ -12,8 +12,11 @@ dependencies {
     testApi(projectTests(":generators:test-generator"))
     testRuntimeOnly(project(":kotlin-reflect"))
     testRuntimeOnly(toolsJar())
+
     testRuntimeOnly(intellijPluginDep("java"))
-    if (isIdeaActive) testRuntimeOnly(files("${rootProject.projectDir}/dist/kotlinc/lib/kotlin-reflect.jar"))
+
+    if (kotlinBuildProperties.isInJpsBuildIdeaSync)
+        testRuntimeOnly(files("${rootProject.projectDir}/dist/kotlinc/lib/kotlin-reflect.jar"))
 }
 
 sourceSets {