[SRU] migration was active, but no RAM info was set

While live-migrating many instances concurrently, libvirt sometimes return internal error: migration was active, but no RAM info was set:
~~~
2022-03-30 06:08:37.197 7 WARNING nova.virt.libvirt.driver [req-5c3296cf-88ee-4af6-ae6a-ddba99935e23 - - - - -] [instance: af339c99-1182-4489-b15c-21e52f50f724] Error monitoring migration: internal error: migration was active, but no RAM info was set: libvirt.libvirtError: internal error: migration was active, but no RAM info was set
~~~

From upstream bug: https://bugzilla.redhat.com/show_bug.cgi?id=2074205

[Impact]

 * Effects of this bug are mostly observed in large scale clusters with a lot of live migration activity.
 * Has second order effects for consumers of migration monitor such as libvirt and openstack.

[Test Case]
Steps to Reproduce:
1. live evacuate a compute
2. live migration of one or more instances fails with the above error

N.B Due to the nature of this bug it is difficult consistently reproduce.

[Where problems could occur]
 * In the event of a regression the migration monitor may report an inconsistent state.