Escape literal backslashes in f-strings to fix syntax warnings

[deFractal]

This escapes backslashes which aren't part of an escape sequence in f-strings, to fix instances of SyntaxWarning in a few files:

masky/core.py:108: SyntaxWarning: invalid escape sequence '\{'
  f"Start processing PFX of the user '{user_data.domain}\{user_data.name}'"
masky/core.py:112: SyntaxWarning: invalid escape sequence '\{'
  f"Fail to process gathered certificate related to the user '{user_data.domain}\{user_data.name}'"
masky/core.py:116: SyntaxWarning: invalid escape sequence '\{'
  f"End processing PFX of the user '{user_data.domain}\{user_data.name}'"
masky/lib/cert/auth.py:428: SyntaxWarning: invalid escape sequence '\{'
  f"Gathered NT hash for the user '{domain}\{username}': {nt_hash}"
masky/lib/smb.py:105: SyntaxWarning: invalid escape sequence '\{'
  err_msg = f"The user {self.__domain}\{self.__username} is not local administrator on this system"
masky/lib/smb.py:108: SyntaxWarning: invalid escape sequence '\{'
  err_msg = f"The provided credentials for the user '{self.__domain}\{self.__username}' are invalids or the user does not exist"
masky/lib/smb.py:295: SyntaxWarning: invalid escape sequence '\p'
  np_bind = f"ncacn_np:{target_host}[\pipe\svcctl]"
masky/ui/main.py:20: SyntaxWarning: invalid escape sequence '\/'
  """
masky/ui/options.py:164: SyntaxWarning: invalid escape sequence '\C'
  help="Certificate Authority Name (SERVER\CA_NAME)",

In main,py, it also combines a triple-quoted r-string and a trip-quoted f-string to align all but the last line of the ASCII art in the source code while fixing a couple of the aforementioned backslash escapes.

[rtpt-romankarwacik]

One backslash escape is missing:

diff --git a/masky/lib/smb.py b/masky/lib/smb.py
index 5730293..dc56e9b 100644
--- a/masky/lib/smb.py
+++ b/masky/lib/smb.py
@@ -292,7 +292,7 @@ class Smb:
         return rslt
 
     def __init_rpc(self, target_host):
-        np_bind = f"ncacn_np:{target_host}[\pipe\svcctl]"
+        np_bind = f"ncacn_np:{target_host}[\\pipe\\svcctl]"
         self.__rpc_con = transport.DCERPCTransportFactory(np_bind)
         self.__rpc_con.set_dport(self.__port)
         self.__rpc_con.setRemoteHost(target_host)