I followed the instructions, but the /etc/localtime doesn’t update.
root@f82708db96e1:/# ls -al /etc/localtime
lrwxrwxrwx 1 root root 27 Oct 5 05:56 /etc/localtime -> /usr/share/zoneinfo/Etc/UTC
root@f82708db96e1:/# echo $TZ
Europe/Dublin
root@f82708db96e1:/# date
Tue Oct 12 16:22:29 IST 2021
Notice the $TZ successfully updated, but /etc/localtime did not.