[Form] [3.0] Remove deprecated OptionsResolverInterface

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | yes
| Deprecations? | no
| Tests pass?   | no
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | symfony/symfony-docs#4565

Not sure if is really useful to already open this PR.
I decided to do it after proposing the symfony/symfony-docs#4565 PR which should
probably be reopened on the master branch of the Symfony docs repository.

Feel free to close the PR if it's not revelant for now!