fix deployment with ipv6 management network

[jonathansnell]

The sunbeam bootstrap cannot process an IPv6 CIDR for the management network. It errors out with Error: 400 Client Error: Bad Request for url: http+unix://%2Fvar%2Fsnap%2Fopenstack%2Fcommon%2Fstate%2Fcontrol.socket/core/control and to find out what was causing that, I sniffed the communication using socat and got the following capture:

HTTP/1.1 400 Bad Request\r
Content-Type: application/json\r
X-Content-Type-Options: nosniff\r
Date: Wed, 08 Jan 2025 15:53:11 GMT\r
Content-Length: 203\r
\r
{"type":"error","status":"","status_code":0,"operation":"","error_code":400,"error":"invalid ip:port \"fd00::2:7000\", IPv6 addresses must be surrounded by square brackets","metadata":null}

This pull request should wrap the IP address returned in square brackets when preparing the http address for clusterd. I also added a bootstrap test that checks against an IPv6 private network, cribbed from the existing test.

[hemanthnakkina]

@jonathansnell There are some linting issues fixed in main, can you rebase your patch.

[jonathansnell]

I have rebased it on the latest main