Fix ambiguous argument error

We have this error on deploy:

```
[hero@10.13.210.15] run: git clone --depth=100 --quiet git@github.com:k-bx/dowant.git /tmp/gachette/working_copy/k-bx/dowant.git
[hero@10.13.210.15] run: git fetch --quiet origin
[hero@10.13.210.15] run: git reset --quiet --hard origin/dowant-729-payment-status-mail
[hero@10.13.210.15] out: fatal: ambiguous argument 'origin/dowant-729-payment-status-mail': unknown revision or path not in the working tree.
[hero@10.13.210.15] out: Use '--' to separate paths from revisions
[hero@10.13.210.15] out:

Fatal error: run() received nonzero return code 128 while executing!

Requested: git reset --quiet --hard origin/dowant-729-payment-status-mail
```

I think this will fix it