Add provisioning e2e test

[lentzi90]

We should add a test that provisions and deprovisions a BareMetalHost.
This will require some kind of disk image and potentially an image server if we can not pull it directly from internet.
My suggestion would be to use a small image to avoid unnecessary download times. Nothing too archaic though. It is better that this is well known and tested than that we save seconds and MBs in the CI.

[Rozzii]

/help
/triage accepted

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In response to this:

/help
/triage accepted

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[maxrantil]

/assign