packer-cleanup: remove packer/files/add_centos_user.sh

[benipeled]

The centos user was added as a cloud workaround - we should sync with the cloud team and remove it

[amnonh]

You can try and open a siren issue about it, it will not be easy

[benipeled]

@amnonh would you like to elaborate or refer to the problematic area/requirements? maybe @d-helios?

[d-helios]

@YvanDaSilva @mrVanboy @carlosms can you explain why do we need this user

[carlosms]

Let's not do that in the public repo. Please open an issue in our repo, or send us an email.