Add baremetal node deprovisioning confirm

[shibaPuppy]

User Story

As a [developer/user/operator] I would like to [high level description] for [reasons]
If an operator accidentally reduces the replicas of a machine deployment, many nodes will be deprovisioned at once.

Detailed Description

[A clear and concise description of what you want to happen.]
CAPM3 is a special controller because it controls baremetal nodes.
If the machine is deleted due to a user's mistake, CAPM3 modifies the resources of the bmh and deprovisions the baremetal node.
At this time, it would be good to have a branch that checks whether to remove the dperovisioning image field by checking the value of bmh metadata.label.remove=true by checking an environment variable such as CAPM3_AUTO_REMOVE=true.

Anything else you would like to add:

[Miscellaneous information that will assist in solving the issue.]

/kind feature

[metal3-io-bot]

This issue is currently awaiting triage.
If Metal3.io contributors determine this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.
The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[Rozzii]

Have you tried to use finalizers to block machine deletion? But in any case could you please explain in more detail what do you mean by this:
"At this time, it would be good to have a branch that checks whether to remove the dperovisioning image field by checking the value of bmh metadata.label.remove=true by checking an environment variable such as CAPM3_AUTO_REMOVE=true."

[Rozzii]

/triage needs-information

[dtantsur]

Also note: if you allow a BMH instance to get orphaned, how do you recover from this situation? Especially for users that do not have access to BMH CR's?

[metal3-io-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues will close after an additional 30d of inactivity.

If this issue is safe to close now please do so with /close.

/lifecycle stale

[Rozzii]

@shibaPuppy FYI this Issue is now stale, please provide the requested information otherwise the issue will be deleted.