[NI] Improved testdata after changes in applicabilities

This commits introduces testdata changes, where NI behaviour strictly
improved, after several previous fixes.

For some tests, just WITH_NEW_INFERENCE directive was added. It
indicates, that some of previous commits first introduced error in that
test, and then some other commit fixed it (netting no overall testdata
change). It is preferrably to keep those annotations until we will
migrate to NI completely, to prevent unexpected regressions.

compiler/testData/diagnostics/tests/controlStructures/ForLoopWithExtensionIteratorOnNullable.kt

@@ -18,5 +18,5 @@ class OtherContainer<K>(val k: K) {
 fun test2() {
     val other: OtherContainer<String>? = null
     // Error
-    for (s in <!NI;ITERATOR_MISSING, OI;ITERATOR_ON_NULLABLE!>other<!>) {}
+    for (s in <!ITERATOR_ON_NULLABLE!>other<!>) {}
 }