Remove ignore tag for tests that don't fail any more

Check for execution correctness inside the test
Fix run_external to include compileKotlinAgainstKotlin

backend.native/tests/external/codegen/box/dataClasses/doubleParam.kt

@@ -1,5 +1,5 @@
 // TODO: muted automatically, investigate should it be ran for JS or not
-// IGNORE_BACKEND: JS, NATIVE
+// IGNORE_BACKEND: JS
 
 val NAN = Double.NaN
 

backend.native/tests/external/codegen/box/dataClasses/floatParam.kt

@@ -1,5 +1,5 @@
 // TODO: muted automatically, investigate should it be ran for JS or not
-// IGNORE_BACKEND: JS, NATIVE
+// IGNORE_BACKEND: JS
 
 val NAN = Float.NaN