Different variants depend on aws route53

[fsniper]

Hi,

We are currently trying to use kubify with azure. Looking into the code, cluster.tf shows it's hard depending on route53. People using different variants may want to skip dns configuration, or use their own variant's dns offering like Azure DNS zones.

[afritzler]

There is a possibility to plugin a new DNS provider into kubify. You will need to modify the DNS module[0] and add a new submodule for your DNS provider (Azure) and register in the dns.tf file.

Contributions are welcome.

[0] https://github.com/gardener/kubify/tree/master/modules/dns