Bug#992153: bullseye-pu: package cloud-init/20.4.1-2+deb11u1

[Noah Meyerhans]

> [ Tests ]
> 
> The upstream fix adds a unit test for this issue.  This and the other tests
> pass during package build.

Also note that the patch is included upstream with 21.2-1, which is
currently in unstable and has been tested.

noah