Foreman Maintain

Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=1679129

Description of problem:

`foreman-maintain service stop` fails with below error message:
~_~~~~~~~~~~~~~
/usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain/config.rb:18:in `expand_path': couldn't find HOME environment -- exp
anding `~' (ArgumentError)
from /usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain/config.rb:18:in `initialize'
from /usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain.rb:54:in `new'
from /usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain.rb:54:in `setup'
from /usr/share/gems/gems/foreman_maintain-0.2.11/bin/foreman-maintain:12:in `<top (required)>'
from /usr/bin/foreman-maintain:23:in `load'
from /usr/bin/foreman-maintain:23:in `<main>'
~_~~~~~~~~~~~~~~~~~~~
Observation:

1. $HOME=/root is set by default in both the Satellite 6.3 and Satellite 6.4.

2. If we manually unset the $HOME in Satellite 6.3, foreman-maintain service still works.

3. If we manually unset the $HOME in Satellite 6.4, foreman-maintain service doesn't work.

Version-Release number of selected component (if applicable):
6.4

How reproducible:
Always, when $HOME is unset in Satellite 6.4

Steps to Reproduce:
1. Open Satellite 6.4 terminal and unset the HOME
2. unset HOME
3. foreman-maintain service stop
4. This will fail

Actual results:

foreman-maintain service should work even if HOME is unset as in Satellite 6.3

Expected results:

Fails with below error:

/usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain/config.rb:18:in `expand_path': couldn't find HOME environment -- exp
anding `~' (ArgumentError)
from /usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain/config.rb:18:in `initialize'
from /usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain.rb:54:in `new'
from /usr/share/gems/gems/foreman_maintain-0.2.11/lib/foreman_maintain.rb:54:in `setup'
from /usr/share/gems/gems/foreman_maintain-0.2.11/bin/foreman-maintain:12:in `<top (required)>'
from /usr/bin/foreman-maintain:23:in `load'
from /usr/bin/foreman-maintain:23:in `<main>'

Additional info:

In order to get an offline and consistent backup of the Satellite, the customer uses the custom script to stop the Satellite services before the backup/snapshot starts.