How to run the online tracker for every frame?

In the online demo, the tracker runs on every 4th step because of this if-clause in [online_demo.py](https://github.com/facebookresearch/co-tracker/blob/main/online_demo.py):

```python
if i % model.step == 0 and i != 0:
_process_step(...)
```

Is it possible to run the tracker on every frame somehow?
I tried adjusting the `model.window_len` which ultimately determines `model.step`, but could not figure out a working solution somehow.

Start with online_demo.py and inspect the if-clause around model.step and the _process_step(...) call. Run the online demo to confirm the current every-fourth-step behavior, then determine how to invoke the tracker on every frame while preserving the demo's online tracking behavior. Done means the tracker processes each frame and the demo still runs successfully.

Written by the indexing model from the issue text.