How can I stop my computer time to reset to my local time-zone time?
You can try blocking outgoing connections to UDP port 123 (NTP) with a PF firewall rule such as:

block drop out quick proto udp from any to any port 123

I'm no PF expert, YMMV.

See here for details on how to apply the rule: https://apple.stackexchange.com/a/230556/134740