Do not pack proguard and stripped jars for kotlin-reflect into compiler zip

kotlin-reflect-proguard.jar has different timestamps and shows
difference on each build for the same sources.

The problem was introduced after migrating to Gradle 7.1 where
`libsDir` parameter was removed (https://docs.gradle.org/current/userguide/upgrading_version_6.html#removal_of_basepluginconvention_libsdir_and_basepluginconvention_distsdir).
After that the same variable started to be resolved to `dist` directory.
So this commit reverts the old behaviour.

^KTI-672 Fixed

build.gradle.kts

@@ -96,7 +96,6 @@ extra["ktorExcludesForDaemon"] = listOf(
 
 // TODO: use "by extra()" syntax where possible
 extra["distLibDir"] = project.file(distLibDir)
-extra["libsDir"] = project.file(distLibDir)
 extra["commonLocalDataDir"] = project.file(commonLocalDataDir)
 extra["ideaSandboxDir"] = project.file(ideaSandboxDir)
 extra["ideaPluginDir"] = project.file(ideaPluginDir)

libraries/reflect/build.gradle.kts

@@ -20,13 +20,14 @@ plugins {
     `java-library`
 }
 
+val jarBaseName = property("archivesBaseName") as String
+
 configureJavaOnlyToolchain(JdkMajorVersion.JDK_1_6)
 
 publish()
 
 val core = "$rootDir/core"
 val relocatedCoreSrc = "$buildDir/core-relocated"
-val libsDir = property("libsDir")
 
 val proguardDeps by configurations.creating
 val proguardAdditionalInJars by configurations.creating
@@ -120,7 +121,7 @@ val reflectShadowJar by task<ShadowJar> {
 val stripMetadata by tasks.registering {
     dependsOn(reflectShadowJar)
     val inputJar = provider { reflectShadowJar.get().outputs.files.singleFile }
-    val outputJar = File("$libsDir/kotlin-reflect-stripped.jar")
+    val outputJar = fileFrom(base.libsDirectory.asFile.get(), "kotlin-reflect-stripped.jar")
 
     inputs.file(inputJar).withNormalizer(ClasspathNormalizer::class.java)
 
@@ -138,14 +139,12 @@ val stripMetadata by tasks.registering {
     }
 }
 
-val proguardOutput = "$libsDir/${property("archivesBaseName")}-proguard.jar"
-
 val proguard by task<CacheableProguardTask> {
     dependsOn(stripMetadata)
 
     injars(mapOf("filter" to "!META-INF/versions/**"), stripMetadata.get().outputs.files)
     injars(mapOf("filter" to "!META-INF/**,!**/*.kotlin_builtins"), proguardAdditionalInJars)
-    outjars(proguardOutput)
+    outjars(fileFrom(base.libsDirectory.asFile.get(), "$jarBaseName-$version-proguard.jar"))
 
     javaLauncher.set(project.getToolchainLauncherFor(JdkMajorVersion.JDK_1_6))
     libraryjars(mapOf("filter" to "!META-INF/versions/**"), proguardDeps)