Prohibit JVM target 1.6

But still compile stdlib, reflect, kotlin.test and scripting runtimes
with JVM target 1.6 to simplify migration from Kotlin 1.6 to 1.7.

 #KT-45165 Fixed

libraries/tools/script-runtime/build.gradle

@@ -8,6 +8,7 @@ configurePublishing(project)
 
 dependencies {
     compileOnly kotlinStdlib()
+    kotlinCompilerClasspath project(':libraries:tools:stdlib-compiler-classpath')
 }
 
 sourceSets {