Add support for Hetzner Cloud Arm Server Types

[apricote]

What type of PR is this?

/kind feature
/area provider/hetzner

Which issue(s) this PR fixes:

Adds support for new APIs and behaviours related to the newly introduced Hetzner Cloud Arm Server Types

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[x13n]

/assign @LKaemmerling @4ND3R50N

Can you review this?

[k8s-ci-robot]

@x13n: GitHub didn't allow me to assign the following users: LKaemmerling, 4ND3R50N.

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In response to this:

/assign @LKaemmerling @4ND3R50N

Can you review this?

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: apricote, LKaemmerling

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• cluster-autoscaler/cloudprovider/hetzner/OWNERS [apricote]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[LKaemmerling]

@x13n This is fine from my side.

[x13n]

Thanks! LGTMing on your behalf then (since you're not technically a k8s org member):

/lgtm