chore(typo): fix comment (microsoft#45016)

Author: jjangga0214

src/compiler/checker.ts

@@ -15161,7 +15161,7 @@ namespace ts {
             let extraTypes: Type[] | undefined;
             // We loop here for an immediately nested conditional type in the false position, effectively treating
             // types of the form 'A extends B ? X : C extends D ? Y : E extends F ? Z : ...' as a single construct for
-            // purposes of resolution. This means such types aren't subject to the instatiation depth limiter.
+            // purposes of resolution. This means such types aren't subject to the instantiation depth limiter.
             while (true) {
                 const isUnwrapped = isTypicalNondistributiveConditional(root);
                 const checkType = instantiateType(unwrapNondistributiveConditionalTuple(root, getActualTypeVariable(root.checkType)), mapper);