Remove directives that have no effect from bytecode text tests

All bytecode text tests are run with stdlib in the classpath and only
for JVM backend, therefore directives WITH_RUNTIME, TARGET_BACKEND,
IGNORE_BACKEND are not needed

compiler/testData/codegen/bytecodeText/nullCheckOptimization/kt12839.kt

@@ -1,5 +1,3 @@
-// WITH_RUNTIME
-
 fun test() {
     val value = System.getProperty("key")
     if (value != null) {
@@ -8,4 +6,4 @@ fun test() {
 }
 
 // 1 IFNULL
-// 0 IFNONNULL
+// 0 IFNONNULL