Add default for backupninja_backup_host for backward compatibility

Change-Id: I1d65b11a5db1e21eeddab27b3518f1204b303b65
Related-Prod: PROD-29006 (PROD:29006)
(cherry picked from commit f6b728ece3997e235a7088e815f12d4df0fdc34e)
1 file changed