add virtualization debug to troubleshooting doc (#1575)

Signed-off-by: Wesley Hayutin <weshayutin@gmail.com>

docs/TROUBLESHOOTING.md

@@ -9,6 +9,7 @@ If you need help, first search if there is [already an issue filed](https://issu
 1. [OADP must-gather](https://docs.openshift.com/container-platform/latest/backup_and_restore/application_backup_and_restore/troubleshooting.html#migration-using-must-gather_oadp-troubleshooting)
 1. [Debugging Failed Backups](#debugging-failed-backups)
 1. [Debugging Failed Restores](#debugging-failed-restores)
+1. [Debugging OpenShift Virtualization backup/restore](virtualization_troubleshooting.md)
 1. [Debugging Data Mover (OADP 1.2 or below)](https://github.com/migtools/volume-snapshot-mover/blob/master/docs/troubleshooting.md)
 1. [OpenShift ROSA STS and OADP installation](https://github.com/rh-mobb/documentation/blob/main/content/docs/misc/oadp/rosa-sts/_index.md)
 1. [Common Issues and Misconfigurations](#common-issues-and-misconfigurations)