n-c-c charm causes non DISA-STIG compliance

[Jeff Hillman]

ubuntu 20.04.5
juju 2.9.37
charm latest/stable rev CH:566
nova-c-c 21.2.4

When running `sudo usg fix disa_stig` against an ubuntu 20.04.5 machine, it becomes DISA-STIG compliant.

running `juju add-machine <user>@<ip>` and then `juju deploy nova-cloud-controller --to 0` causes DISA-STIG to no longer be compliant

Specifically, running a diff against the compliant results `sudo usg audit disa_stig` and then against the newly deployed nova-cloud-controller charm causes the following diff:

```
- <rule-result idref="permissions_local_var_log" time="2022-11-16T15:38:14" severity="medium" weight="1.000000">
- <result>pass</result>
+ <rule-result idref="permissions_local_var_log" time="2022-11-17T21:17:08" severity="medium" weight="1.000000">
+ <result>fail</result>

```

nova-cloud-controller charm is breaking the permissions_local_var_log DISA-STIG compliance.