docs(*) fix dangling links in API docs (#16632)

* docs(animations): fix links to `Component` animations

* docs(core): fix links to `ReflectiveInjector` methods

The `resolve` and other methods were moved from the
`Injector` to the `ReflectiveInjector`.

* docs(core): fix links to `Renderer`

The local links were assuming that that methods were on the
current document (e.g. `RootRenderer`), but they are actually
on the `Renderer` class.

* docs(router): fix links to methods

* docs(forms): fix links to methods

* docs(core): fix links to methods

* docs(router): fix API page links and an internal link

packages/forms/src/directives/reactive_directives/form_group_name.ts

@@ -128,7 +128,7 @@ export const formArrayNameProvider: any = {
  * status is re-calculated.
  *
  * **Add new controls**: You can add new controls to the {@link FormArray} dynamically by
- * calling its {@link FormArray.push} method.
+ * calling its {@link FormArray#push} method.
  *  Ex: `this.form.get('cities').push(new FormControl());`
  *
  * ### Example