Add hmac import to wyng script

[keeperofdakeys]

On python 3.9 on Almalinux 9 (RHEL 9 based), the hmac module is not available in python without importing it. Add import so script will function.

(Do other OSes like Qubes import hmac automatically for you?).

[root@host wyng-backup]# cat /etc/redhat-release
AlmaLinux release 9.1 (Lime Lynx)
[root@tt20 wyng-backup]# python3.9
Python 3.9.14 (main, Nov  7 2022, 00:00:00)
[GCC 11.3.1 20220421 (Red Hat 11.3.1-2)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> dir(hmac)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'hmac' is not defined
>>>

[tasket]

Thanks!