fix(xo-server/backup NG): fix error condition (#3939)

Fix #3875

CHANGELOG.unreleased.md

@@ -6,6 +6,7 @@
 
 - [Host] Show the host's memory usage instead of the sum of the VMs' memory usage (PR [#3924](https://github.com/vatesfr/xen-orchestra/pull/3924))
 - [SAML] Make `AssertionConsumerServiceURL` matches the callback URL
+- [Backup NG] Correctly delete broken VHD chains [#3875](https://github.com/vatesfr/xen-orchestra/issues/3875) (PR [#3939](https://github.com/vatesfr/xen-orchestra/pull/3939))
 
 ### Released packages
 

packages/xo-server/src/xo-mixins/backups-ng/index.js

@@ -1365,10 +1365,9 @@ export default class BackupNg {
 
                   return
                 } catch (error) {
-                  if (
-                    !(error instanceof AssertionError) ||
-                    error?.code === 'ENOENT'
-                  ) {
+                  const corruptedVhdOrMissingParent =
+                    error instanceof AssertionError || error?.code === 'ENOENT'
+                  if (!corruptedVhdOrMissingParent) {
                     throw error
                   }
                 }