[cleaner] Use "hostname -f" in HostnamePrepper

HostnamePrepper should always be fed by FQDN to ensure domain names are
recognized properly.

This is important esp. when:
- /etc/hosts is empty
- "hostname" contains shortname only
- "hostname -f" contains FQDN

Resolves: #4022
Closes: #4026

Signed-off-by: Pavel Moravec <[email protected]>

Author: pmoravec

sos/cleaner/preppers/hostname.py

@@ -29,7 +29,7 @@ def _get_items_for_hostname(self, archive):
         items = []
         _file = 'hostname'
         if archive.is_sos:
-            _file = 'sos_commands/host/hostname'
+            _file = 'sos_commands/host/hostname_-f'
         elif archive.is_insights:
             _file = 'data/insights_commands/hostname_-f'