Do no set automatedCleaningMode in BareMetalHosts

What does this MR do and why?

remove automatedCleaningMode from BareMetalHosts in sample values files. This value should be driven by cluster.capo.automatedCleaningMode instead, that is setting this field in Metal3MachineTemplates (and then copied to BMH by capm3 controller)

s-c-c has been updated in sylva-projects/sylva-elements/helm-charts/sylva-capi-cluster!329 (merged) to provide a default that should be relevant in most cases (as it enable the reuse of nodes storage on upgrades). We should not encourage user to tweak that value, unless they have strong reasons to do so.

Fixes: #1160 (closed)