Filter undefined from binding elements with initialisers without undefined in the type (#38122)

* Filter undefined from binding elts w/o undefined-containing inits

* use getTypeOfInitializer instead

* improve comment based on Wesleys suggestion

tests/cases/compiler/contextualTypeForInitalizedVariablesFiltersUndefined.ts

@@ -6,3 +6,4 @@ const fAnnotated: typeof fInferred = ({ a = 0 } = {}) => a;
 
 declare var t: { s: string } | undefined;
 const { s } = t;
+function fst({ s } = t) { }