Check end-of-life version of deprecated features

Extend `_warn_deprecated` with a mandatory `version` parameter and raise an `InternalError` if the current fairseq2 version is at or above the specified version.

```python
from packaging.Version

def _warn_deprecated(msg: str, eol_version: Version) -> None:
if fairseq2.__version__ >= eol_version:
raise InternalError("Deprecated feature not removed at or after end-of-life version")
```