Fix maven build + ~50 compiler tests broken by UNUSED_PARAMETER in main

libraries/tools/kotlin-maven-plugin-test/src/it/test-plugins/use-test-extension/src/main/kotlin/main.kt

@@ -1,5 +1,5 @@
 package org.jetbrains.kotlin.test
 
-fun main(args: Array<String>) {
+fun main() {
     println("OK")
 }

libraries/tools/kotlin-maven-plugin/src/it/simple/src/main/kotlin/yo.kt

@@ -1,2 +1,2 @@
-fun main(vararg args: String) {
+fun main() {
 }