refactor(forms): remove a TODO and simplify update on <select> mutations

Remove an unnecessary TODO comment. The native `<select>` tracks its
`value` by keeping track of the selected `<option>`. Thus if the value
was set *before* the corresponding option is created, the `<select>`
will ignore it, but the framework doesn't know that and will cache the
bound value anyways. Therefore, checking if the value changed since it
was last bound when the mutation that creates the selected `<option>`
occurs would in fact prevent a needed update, leaving the `<select>` and
field values out of sync.

Furthermore, we know the control type is a native `<select>` element, so
we can update its value directly instead of going through
`updateNativeControl()` which would perform a redundant input type
check.

packages/core/src/render3/instructions/control.ts

@@ -391,9 +391,7 @@ function observeSelectMutations(
 ): MutationObserver {
   const observer = new MutationObserver((mutations) => {
     if (mutations.some((m) => isRelevantSelectMutation(m))) {
-      // TODO: https://github.com/orgs/angular/projects/60/views/1?pane=issue&itemId=131711472
-      // * check if bindings changed before writing.
-      setNativeControlValue(select, controlDirective.state().value());
+      select.value = controlDirective.state().value();
     }
   });
   observer.observe(select, {