find_address_timeout removed: why?

**Describe the issue**:

The `find_address_timeout` argument was removed from `ecs.Task` in [7c84ad7](https://github.com/dask/dask-cloudprovider/commit/26a6284ab9185a7f78c22b12e68178dd47c84ad7) with no apparent replacement.

**Minimal Complete Verifiable Example**:

```python
Task(find_address_timeout=180, ...)
```

**Anything else we need to know?**:

If specifying this argument is no longer the correct way to prevent timeouts, then what is? That commit did not update any documentation regarding this logic.