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/capturedVarsOptimization/capturedVarsOfSize2.kt

@@ -1,5 +1,3 @@
-// WITH_RUNTIME
-
 fun box(): String {
     var xl = 0L     // Long, size 2
     var xi = 0      // Int, size 1
@@ -22,4 +20,4 @@ fun box(): String {
     return "OK"
 }
 
-// 0 NEW
+// 0 NEW