Issue with digchecker when dig is not installed

[Turgon37]

FileNotFoundError: [Errno 2] No such file or directory: 'dig': 'dig'
ERROR [ipcheck] : [Errno 2] No such file or directory: 'dig': 'dig'
Traceback (most recent call last):
  File "/opt/IpCheck/ipcheckadvanced/loader.py", line 193, in pushEvent
    if not ext.handle(event, type, data):
  File "/opt/IpCheck/ipcheckadvanced/extension/digchecker.py", line 144, in handle
    out = subprocess.check_output(cmd)
  File "/usr/lib/python3.7/subprocess.py", line 395, in check_output
    **kwargs).stdout
  File "/usr/lib/python3.7/subprocess.py", line 472, in run
    with Popen(*popenargs, **kwargs) as process:
  File "/usr/lib/python3.7/subprocess.py", line 775, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.7/subprocess.py", line 1522, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'dig': 'dig'