Add runtime dependency on experimental coroutines to :kotlin-scripting-compiler-impl

This is needed to keep compatibility with old gradle versions which
  are steel using kotlin 1.2 with experimental coroutines

plugins/scripting/scripting-compiler-impl/build.gradle.kts

@@ -25,6 +25,7 @@ dependencies {
     compileOnly(intellijDep()) { includeJars("platform-api") }
 
     runtimeOnly(project(":kotlin-reflect"))
+    runtimeOnly( "org.jetbrains.kotlin:kotlin-coroutines-experimental-compat:1.4.20")
 
     testCompile(project(":compiler:frontend"))
     testCompile(project(":compiler:plugin-api"))