Fix missing refresh_authorized_keys.timer

[scadu]

After merging
#1597, goss test started failing with missing refresh_authorized_keys.timer.

Looking closer, it looks like Packer overrides /tmp/conf directory with content of ../shared/conf.

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Verifying base AMI built with this change, we got the timer back:

systemctl status refresh_authorized_keys.timer
○ refresh_authorized_keys.timer - Download ssh authorized_keys file from s3
     Loaded: loaded (/etc/systemd/system/refresh_authorized_keys.timer; disabled; preset: disabled)
     Active: inactive (dead)
    Trigger: n/a
   Triggers: ● refresh_authorized_keys.service

[JoeColeman95]

I think just adding trailing slashes to the src and dest should merge but not going to nit-pick as I assume it's been tested and don't want to block

[scadu]

I think just adding trailing slashes to the src and dest should merge but not going to nit-pick as I assume it's been tested and don't want to block

@JoeColeman95 I hoped it'd worked that way. Tested it now – works fine! Thanks for flagging.