fix(backups): pass type to Xapi#getRecord

Fixes #7131

Introduced by 37b211376

@xen-orchestra/backups/_runners/_vmRunners/FullXapi.mjs

@@ -39,7 +39,8 @@ export const FullXapi = class FullXapiVmBackupRunner extends AbstractXapi {
     const vdis = await exportedVm.$getDisks()
     let maxStreamLength = 1024 * 1024 // Ovf file and tar headers are a few KB, let's stay safe
     for (const vdiRef of vdis) {
-      const vdi = await this._xapi.getRecord(vdiRef)
+      const vdi = await this._xapi.getRecord('VDI', vdiRef)
+
       // at most the xva will take the physical usage of the disk
       // the resulting stream can be smaller due to the smaller block size for xva than vhd, and compression of xcp-ng
       maxStreamLength += vdi.physical_utilisation

CHANGELOG.unreleased.md

@@ -12,6 +12,7 @@
 > Users must be able to say: “I had this issue, happy to know it's fixed”
 
 - [Netbox] Fix "The selected cluster is not assigned to this site" error [Forum#7887](https://xcp-ng.org/forum/topic/7887) (PR [#7124](https://github.com/vatesfr/xen-orchestra/pull/7124))
+- [Backups] Fix `MESSAGE_METHOD_UNKNOWN` during full backup [Forum#7894](https://xcp-ng.org/forum/topic/7894)(PR [#7139](https://github.com/vatesfr/xen-orchestra/pull/7139))
 
 ### Packages to release
 
@@ -29,6 +30,7 @@
 
 <!--packages-start-->
 
+- @xen-orchestra/backups patch
 - xo-cli minor
 - xo-server-netbox patch
 - xo-web patch