[Native] Drop LLDB_TRACE test directive

This directive doesn't have a lot of meaning. It is always set this
way that we are getting text file with the same name as test file.

native/native.tests/testData/lldb/kt42208WithVariable.kt

@@ -1,5 +1,5 @@
 // KIND: STANDALONE_LLDB
-// LLDB_TRACE: kt42208WithVariable.txt
+
 // FILE: kt42208-1.kt
 fun main() {
     val a = foo()