remove subdomaincenter

reason: removing due to output quality, for example:

```
172.hackerone.com
52.227.hackerone.com
155.227.hackerone.com
continuous.hackerone.com
cs408517.hackerone.com
opendata.hackerone.com
28.hackerone.com
deposits.ns.hackerone.com
40.227.hackerone.com
91.227.hackerone.com
itap.hackerone.com
```