Fix fail to start backup after stopping a backup

When there is an abrupt disconnect (target is shut down,
network glitch), the backup_in_progress flag remains,
resulting in error to start a new backup process.

This commit adds a new condition to check if backup_in_progress
flag was created less than 20 minutes ago, so block the process
otherwise, ignore the flag and continue the backup process.

Test Plan:
- PASS: Run backup process AIO-SX without backup_in_progress flag
- PASS: Run backup process AIO-SX with backup_in_progress flag
  (before 20 minutes since the last backup interrupted)
- PASS: Run backup process AIO-SX with backup_in_progress flag
  (after 20 minutes since the last backup interrupted)

Closes-Bug: 2002128
Signed-off-by: Guilherme Schons <guilherme.dossantosschons@windriver.com>
Change-Id: I3f51c41005208e96d747b1c89931471b218f709b

playbookconfig/src/playbooks/roles/backup/prepare-env/tasks/main.yml

@@ -14,9 +14,17 @@
     path: "{{ backup_in_progress_flag }}"
   register: backup_in_progress
 
-- name: Fail if backup is already in progress
-  fail:
-    msg: "Backup is already in progress!"
+- block:
+  - name: Get unix timestamp from the system
+    shell: "date +%s"
+    register: unix_timestamp
+
+  - name: Fail if backup is already in progress for less than 20 minutes
+    fail:
+      msg: >-
+        A backup has already been started less than 20 minutes ago.
+        Wait to start a new backup or manually remove the backup flag in {{ backup_in_progress_flag }}
+    when: (unix_timestamp.stdout | float - backup_in_progress.stat.ctime) < 1200
   when: backup_in_progress.stat.exists
 
 - name: Check if it is the active controller