[Installer][baremetal][metal3] The baremetal IPI installer fails on delete cluster with: failed to clean baremetal bootstrap storage pool

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[root@openshift-jumpserver-0 ~]# ./openshift-baremetal-install version
./openshift-baremetal-install 4.7.5
built from commit e15f17c958b4a04e770c0cfe758ca69452874508
release image quay.io/openshift-release-dev/ocp-release@sha256:0a4c44daf1666f069258aa983a66afa2f3998b78ced79faa6174e0a0f438f0a5
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After a successful installation, the libvirt bootstrap VM and the storage pool are already deleted by the installer:
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[root@openshift-jumpserver-0 ~]# virsh pool-list
 Name      State    Autostart
-------------------------------
 default   active   yes

[root@openshift-jumpserver-0 ~]# virsh list --all
 Id   Name   State
--------------------

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Therefore, when someone tries to destroy the cluster, it fails:
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[root@openshift-jumpserver-0 ~]# ./openshift-baremetal-install destroy cluster  --log-level=debug --dir=openshift-install
DEBUG OpenShift Installer 4.7.5                    
DEBUG Built from commit e15f17c958b4a04e770c0cfe758ca69452874508 
DEBUG Deleting bare metal resources                
DEBUG Deleting baremetal bootstrap volumes         
FATAL Failed to destroy cluster: failed to clean baremetal bootstrap storage pool: get storage pool "ipi-cluster-kfczp-bootstrap": virError(Code=49, Domain=18, Message='Storage pool not found: no storage pool with matching name 'ipi-cluster-kfczp-bootstrap'') 
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https://github.com/openshift/installer/blob/fae650e24e7036b333b2b2d9dfb5a08a29cd07b1/pkg/destroy/baremetal/baremetal.go#L59

I do not think that we should throw a FATAL error when a resource which we want to clean up cannot be found. If the pool cannot be found, this also indicates that the storage should be gone. Thus, simply log a warning or info and continue the operation.