Foreman Maintain

Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=1769459

Description of problem:

While taking backup with foreman-maintain on satellite which is configured with infoblox is failing with below error:

--------------------------------------------------------------------------------
Backup config files:
- Collecting config files to backup [FAIL]
Couldn't find DHCP Configuration file
--------------------------------------------------------------------------------

This is quite obvious because if we configure external DHCP server or infoblox /etc/dhcp/dhcpd.conf file will not get created. Hence foreman-maintain is failing to backup dhcp config file.

Version-Release number of selected component (if applicable):
6.5

How reproducible:

100%
Steps to Reproduce:
1. Configure satellite with infoblox according https://access.redhat.com/documentation/en-us/red_hat_satellite/6.5/html/provisioning_guide/chap-infoblox-integration
2. Try to backup satellite

1. foreman-maintain backup offline -s --features all /var/satellite/backup
   3.

Actual results:

Failed with below error:

--------------------------------------------------------------------------------
Backup config files:
- Collecting config files to backup [FAIL]
Couldn't find DHCP Configuration file
--------------------------------------------------------------------------------

---------------------------------
D, [2019-11-06 10:24:08-0500 #6054] DEBUG -- : foreman proxy content module detected: foreman_proxy_content
E, [2019-11-06 10:24:08-0500 #6054] ERROR -- : Couldn't find DHCP Configuration file (RuntimeError)
/usr/share/gems/gems/foreman_maintain-0.3.4/definitions/features/foreman_proxy.rb:186:in `lookup_dhcpd_config_file'
/usr/share/gems/gems/foreman_maintain-0.3.4/definitions/features/foreman_proxy.rb:93:in `dhcpd_config_file'
/usr/share/gems/gems/foreman_maintain-0.3.4/definitions/features/foreman_proxy.rb:63:in `config_files'
/usr/share/gems/gems/foreman_maintain-0.3.4/definitions/procedures/backup/config_files.rb:32:in `config_files'
/usr/share/gems/gems/foreman_maintain-0.3.4/definitions/procedures/backup/config_files.rb:20:in `block in run'
/usr/share/gems/gems/foreman_maintain-0.3.4/lib/foreman_maintain/reporter/cli_reporter.rb:141:in `with_spinner'
/usr/share/gems/gems/foreman_maintain-0.3.4/definitions/procedures/backup/config_files.rb:19:in `run'

Expected results:

foreman-maintain should check if DHCP is configured with infoblox and act accordingly.
Additional info: