Build: enable -Werror in stdlib/core/compiler/plugins modules

Exclude modules where there are still warnings in an explicitly declared
variable `tasksWithWarnings`.

Also remove "-progressive" from compiler arguments in modules which are
built with non-latest language version, as the warning about that leads
to an error with -Werror.

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

@@ -47,7 +47,7 @@ tasks.withType<org.jetbrains.kotlin.gradle.dsl.KotlinCompile<*>> {
     kotlinOptions {
         languageVersion = "1.3"
         apiVersion = "1.3"
-        freeCompilerArgs += "-Xskip-metadata-version-check"
+        freeCompilerArgs = freeCompilerArgs - "-progressive" + "-Xskip-metadata-version-check"
     }
 }