fix(xapi/VM_snapshot): VM#refresh_snapshots does not exist

Fixes xoa-support#3587

@xen-orchestra/xapi/src/vm.js

@@ -452,6 +452,7 @@ module.exports = class Vm {
     do {
       if (!vm.tags.includes('xo-disable-quiesce')) {
         try {
+          let { snapshots } = vm
           ref = await pRetry(
             async () => {
               try {
@@ -463,13 +464,13 @@ module.exports = class Vm {
                 // detect and remove new broken snapshots
                 //
                 // see https://github.com/vatesfr/xen-orchestra/issues/3936
-                const prevSnapshotRefs = new Set(vm.snapshots)
+                const prevSnapshotRefs = new Set(snapshots)
                 const snapshotNameLabelPrefix = `Snapshot of ${vm.uuid} [`
-                await vm.refresh_snapshots()
+                snapshots = await this.getField('VM', vm.$ref, 'snapshots')
                 const createdSnapshots = (
                   await this.getRecords(
                     'VM',
-                    vm.snapshots.filter(_ => !prevSnapshotRefs.has(_))
+                    snapshots.filter(_ => !prevSnapshotRefs.has(_))
                   )
                 ).filter(_ => _.name_label.startsWith(snapshotNameLabelPrefix))
                 // be safe: only delete if there was a single match

CHANGELOG.unreleased.md

@@ -14,6 +14,7 @@
 > Users must be able to say: “I had this issue, happy to know it's fixed”
 
 - [Backup restore] Generate new MAC addresses is disabled by default (PR [#5707](https://github.com/vatesfr/xen-orchestra/pull/5707))
+- [Backup] Fix `vm.refresh_snapshots is not a function` error
 
 ### Packages to release
 
@@ -32,5 +33,7 @@
 >
 > In case of conflict, the highest (lowest in previous list) `$version` wins.
 
+- @xen-orchestra/xapi patch
 - xo-server-load-balancer minor
+- xo-server patch
 - xo-web patch