[JS IR BE] Unmute tests

compiler/testData/codegen/box/unaryOp/call.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun box(): String {
     val a1: Byte = 1.unaryMinus()
     val a2: Short = 1.unaryMinus()

compiler/testData/codegen/box/unaryOp/callNullable.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun box(): String {
     val a1: Byte? = 1.unaryMinus()
     val a2: Short? = 1.unaryMinus()

compiler/testData/codegen/box/unaryOp/longOverflow.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JS_IR
 fun box(): String {
     val a: Long = -(1 shl 31)
     if (a != -2147483648L) return "fail: in this case we should add to ints and than cast the result to long - overflow expected"