[FE] Add clear warning about future changes about nullability of safe call with non nullable receiver

^KT-46860

js/js.ast/src/org/jetbrains/kotlin/js/backend/ast/jsScopes.kt

@@ -61,7 +61,7 @@ open class JsDeclarationScope(parent: JsScope, description: String, useParentSco
          * Safe call is necessary, because hasOwnName can be called
          * in constructor before labelName is initialized (see KT-4394)
          */
-        @Suppress("UNNECESSARY_SAFE_CALL")
+        @Suppress("UNNECESSARY_SAFE_CALL", "SAFE_CALL_WILL_CHANGE_NULLABILITY")
         override fun hasOwnName(name: String): Boolean =
                 name in RESERVED_WORDS
                 || name == ident