Remove experimental coroutines opt-in from build scripts

It has no effect in Kotlin 1.3

Only enable coroutines if '-ReleaseCoroutines' is used

libraries/scripting/common/build.gradle.kts

@@ -1,4 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.Coroutines
 
 plugins {
     kotlin("jvm")
@@ -19,8 +18,6 @@ sourceSets {
     "test" {}
 }
 
-kotlin.experimental.coroutines = Coroutines.ENABLE
-
 val jar = runtimeJar()
 val sourcesJar = sourcesJar()
 val javadocJar = javadocJar()

libraries/scripting/jvm-host/build.gradle.kts

@@ -1,6 +1,4 @@
 
-import org.jetbrains.kotlin.gradle.dsl.Coroutines
-
 plugins {
     kotlin("jvm")
     id("jps-compatible")
@@ -25,8 +23,6 @@ sourceSets {
     "test" { projectDefault() }
 }
 
-kotlin.experimental.coroutines = Coroutines.ENABLE
-
 standardPublicJars()
 
 publish()

libraries/scripting/jvm/build.gradle.kts

@@ -1,4 +1,3 @@
-import org.jetbrains.kotlin.gradle.dsl.Coroutines
 
 plugins {
     kotlin("jvm")
@@ -18,8 +17,6 @@ sourceSets {
     "test" {}
 }
 
-kotlin.experimental.coroutines = Coroutines.ENABLE
-
 val jar = runtimeJar()
 val sourcesJar = sourcesJar()
 val javadocJar = javadocJar()