interface(loopback): add check for same ipv4_address_secondary

[alagoutte]

When using the following code and repeat twice, the second time (like for ansible with idempotent) you get an 500 error

Ran into exception: 'GENERIC OPERATION ERROR: Internal service error.\n: Code: 500'. Closing session.

import urllib3
from pyaoscx.session import Session
from pyaoscx.pyaoscx_factory import PyaoscxFactory
from pyaoscx.vlan import Vlan
from pyaoscx.interface import Interface
from pyaoscx.device import Device

version = "10.09"
switch_ip = "10.200.11.147"

urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
s = Session(switch_ip, version)
s.open("admin", "MyPassword")

try:
    device = Device(s)
    
    ipv4 = ["10.23.23.1/24", "10.123.23.1/24"]

    #print("ipv4 {0}".format(ipv4))
    loopback_interface = device.interface("loopback23")
    loopback_interface.configure_loopback(
                ipv4=ipv4,
                vrf = None
    )
except Exception as error:
    print("Ran into exception: {0}. Closing session.".format(error))

finally:
    s.close()

add simple check for don't append with same ip the ipv4_secondary attribut