[JS IR BE] Remove unnecesary println from tests

js/js.translator/testData/box/expression/when/exhaustiveCheckException.kt

@@ -1,9 +1,8 @@
 // IGNORE_BACKEND: JS_IR
-// KJS_WITH_FULL_RUNTIME
 // EXPECTED_REACHABLE_NODES: 1323
 fun <T> checkThrown(x: T, block: (T) -> Any?): Unit? {
     return try {
-        println((block(x) ?: "").toString())
+        block(x)
         null
     }
     catch (e: NoWhenBranchMatchedException) {
@@ -13,7 +12,7 @@ fun <T> checkThrown(x: T, block: (T) -> Any?): Unit? {
 
 fun <T> checkNotThrown(x: T, block: (T) -> Any?): Unit? {
     return try {
-        println((block(x) ?: "").toString())
+        block(x)
         Unit
     }
     catch (e: NoWhenBranchMatchedException) {