[CI] Docker linter checks nothing

### Describe the bug, including details regarding any error messages, version, and platform.

We have a Hadolint configuration for pre-commit:

https://github.com/apache/arrow/blob/59267e0e3bd2f32540cb0c6dd3bd45cba0cb9497/.pre-commit-config.yaml#L32-L37

But it doesn't check any files because `hadolint-docker` uses `types: ["dockerfile"]` but we use `ci/docker/*.dockerfile` and pre-commit uses `.Dockerfile` for extension for `dockerfile` type:

* https://github.com/hadolint/hadolint/blob/742b76e3b9b4d45d6716771b0f1fae2fa0069104/.pre-commit-hooks.yaml#L6
* https://github.com/pre-commit/identify/blob/0651fca53e7ef7edab19cad41f6ee4fe89375b55/tests/identify_test.py#L159-L161

### Component(s)

Continuous Integration