custom UID for a user in azure builder

[Shashank]

Hi,

I want to make custom image in azure. I want to use `centos` username with a fixed UID.

Now while creating the custom image, the packer makes an ssh connection using the centos user.
Since the ssh connection is active we can't change the UID of centos user in our custom script.

Is there any way using provisioners i.e before making the SSH connection run "usermod" command on the base image machine?