fixed errors and suppressed deprecation warning

[fuggles-5555]

Running patator gave me the following errors:

patator/patator.py:27: SyntaxWarning: invalid escape sequence '\w'
  '''
patator/patator.py:2674: SyntaxWarning: invalid escape sequence '\w'
  ('prompt_re', 'regular expression to match prompts [\w+:]'),
patator/patator.py:2687: SyntaxWarning: invalid escape sequence '\w'
  def execute(self, host, port='23', inputs=None, prompt_re='\w+:', timeout='20', persistent='0'):
patator/patator.py:3388: SyntaxWarning: invalid escape sequence '\w'
  ('prompt_re', 'regular expression to match prompts [\w+:]'),
patator/patator.py:3410: SyntaxWarning: invalid escape sequence '\w'
  def execute(self, host, port='513', luser='root', user='', password=None, prompt_re='\w+:', timeout='10', persistent='0'):
patator/patator.py:4281: SyntaxWarning: invalid escape sequence '\d'
  m = re.search(' Authentication only, exit status (\d+)', err)
patator/patator.py:4998: SyntaxWarning: invalid escape sequence '\('
  mesg = 'Handshake returned: %s (%s)' % (re.search('SA=\((.+) LifeType', out).group(1), re.search('\t(.+) Mode Handshake returned', out).group(1))
patator/patator.py:2658: DeprecationWarning: 'telnetlib' is deprecated and slated for removal in Python 3.13
  from telnetlib import Telnet

I appreciate these are only warnings, but I've escaped the SyntaxWarnings in the pull request, and I've suppressed the DeprecationWarning.

The SyntaxWarnings have been fixed by double escaping the mentioned characters.
The DeprecationWarning was fixed by importing the warning library, then catching and ignoring telnetlib warnings.