[Form] added the ability to use a closure for collection item 'options'

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #11467
| License       | MIT
| Doc PR        | in progress

For the Doc PR, I didn't find in the Symfony docs which version something new would go into if accepted, so if someone would like to elaborate on that so I can [add the version it was introduced in to the docs I updated](https://github.com/Limelyte/symfony-docs/commit/b459473e2aa9f983cefdde89dd62fecf7576fa1c), that'd be fantastic!