Fix error on rke2 cluster for Azure

[02bensch]

This addresses and fixes #875
After adding the private_address_only to the schema, we were able to successfully create the resource.

[phillipsj]

I just ran all the tests and they are all passing.

[superseb]

I believe this needs a docs change at https://github.com/rancher/terraform-provider-rancher2/blob/master/docs/resources/machine_config_v2.md?

[02bensch]

@superseb I have added the docs change.
There is however - I believe - some overlap between no_public_ip and private_address_only within the azure_config arguments. Perhaps in future no_public_ip could be removed, in order to align azure_config more closely with amazonec2_config arguments.

[eliyamlevy]

@02bensch I agree that we can probably drop the no_public_ip flag. Seems like overlapping functionality. I'd open another issue for removing it so it's written down somewhere.

[02bensch]

@02bensch I agree that we can probably drop the no_public_ip flag. Seems like overlapping functionality. I'd open another issue for removing it so it's written down somewhere.

@eliyamlevy I have opened #956. I will link the necessary PRs to it when I get a chance.

[eliyamlevy]

@02bensch sounds good. I've passed it along to the right people to get it approved before merging. We also have an internal issue for this but feel free to link yours as well.