[BUG]Salt minion connection to master fails for OS "Microsoft Windows Server Datacenter"

Setup
(Please provide relevant configs and/or SLS files (be sure to remove sensitive info).

Steps to Reproduce the behavior

TypeError: argument of type 'NoneType' is not iterable
Traceback (most recent call last):
  File "C:\VMware\UCP\salt\bin\Scripts\ucp-salt-minion", line 26, in <module>
    salt_minion()
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\scripts.py", line 191, in salt_minion
    minion.start()
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\cli\daemons.py", line 346, in start
    self._real_start()
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\cli\daemons.py", line 358, in _real_start
    self.minion.tune_in()
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\minion.py", line 1065, in tune_in
    self._spawn_minions()
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\minion.py", line 1009, in _spawn_minions
    jid_queue=self.jid_queue)
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\minion.py", line 977, in _create_minion_object
    jid_queue=jid_queue)
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\minion.py", line 1136, in __init__
    self.opts['grains'] = salt.loader.grains(opts)
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\loader.py", line 784, in grains
    ret = funcs[key]()
  File "C:\VMware\UCP\salt\bin\lib\site-packages\salt\grains\core.py", line 1662, in os_data
    if 'Server' in grains['osrelease']:
TypeError: argument of type 'NoneType' is not iterable

Expected behavior
Salt minion should be able to connect to master

Screenshots
Attached screenshot is os info of the machine where the minion is being installed

Versions Report

PASTE HERE
![image](https://user-images.githubusercontent.com/13471183/116521353-7e087400-a8f1-11eb-9735-22b44c864805.png)

Additional context
Add any other context about the problem here.