fix(proxy/backup.run): handle multiple self licenses

See xoa-support#3730

Previous code would fail if the first license returned was already expired.

@xen-orchestra/proxy/src/app/mixins/appliance.mjs

@@ -153,6 +153,10 @@ export default class Appliance {
 
   // A proxy can be bound to a unique license
   getSelfLicense() {
-    return Disposable.use(getUpdater(), _ => _.call('getSelfLicenses').then(licenses => licenses[0]))
+    return Disposable.use(getUpdater(), async updater => {
+      const licenses = await updater.call('getSelfLicenses')
+      const now = Date.now()
+      return licenses.find(({ expires }) => expires === undefined || expires > now)
+    })
   }
 }

@xen-orchestra/proxy/src/app/mixins/backups.mjs

@@ -107,8 +107,8 @@ export default class Backups {
       async function () {
         if (!__DEV__) {
           const license = await app.appliance.getSelfLicense()
-          if (license === undefined || license.expires < Date.now()) {
-            throw new Error('the proxy license is not valid')
+          if (license === undefined) {
+            throw new Error('no valid proxy license')
           }
         }
         return run.apply(this, arguments)