Allow provider to work with self-hosted controllers

[biodrone]

From what I can tell, the underlying import to create a client in go-ztcentral hard sets a bearer-style header. The header for self-hosted controllers needs be be 'X-ZT1-Auth' however, so this just 401s.

Whilst this is an issue with using the TF provider, let me know if this is best opened under the go-ztcentral package to provide an override of some sort? One may already exist but I can't for the life of me figure out how to execute that from the provider level.

I've patched a workaround locally in go-ztcentral so I could submit a PR if you like, although with it being named after ztcentral, perhaps it makes sense to be somewhere else? Not sure but I'm happy to help, just let me know!

[glimberg]

This only works with Central right now. Self hosted controllers aren't supported in the terraform provider at this time, but it's on our radar.

[Joao-1]

Any update about allow provider to work with self-hosted controllers? This module is very useful.