Backup restoration fixes

XXMessengerClient

• Update MessengerRestoreBackup function, so it does not try to clean up storage on failure.

xx-messenger example

• Save restored contact when restoring from backup.
• Destory messenger when restoring backup fails.

requested review from @brunomunizaf

assigned to @darrarski.xx

added 2 commits

• b215df5e - Update MessengerRestoreBackup
• 58f851c4 - Destroy messenger when backup restoration fails

Compare with previous version

changed title from Messenger example - save restored contact (fix) to Backup restoration fixes

changed the description

enabled an automatic merge when the pipeline for 58f851c4 succeeds

mentioned in commit bebb525c

merged