What this PR does / why we need it:
Adding the ssh key name via hetzner secret facilitates use cases where a lot of clusters are created with the same ssh key. Instead of having to specify it every time in the HetznerClusterTemplate object, it can be specified in the secret ones.
On top, this commit introduces default values for the HetznerSecret to allow use cases where all is hard-coded and doesn't have to be specified e.g. in a ClusterClass or in the templates of the cluster object anymore.
What this PR does / why we need it: Adding the ssh key name via hetzner secret facilitates use cases where a lot of clusters are created with the same ssh key. Instead of having to specify it every time in the HetznerClusterTemplate object, it can be specified in the secret ones.
On top, this commit introduces default values for the HetznerSecret to allow use cases where all is hard-coded and doesn't have to be specified e.g. in a ClusterClass or in the templates of the cluster object anymore.
TODOs: