Fix SSH port binding

[treydock]

Fixes #52

From what I can gather the key lookup of PortBinding in network settings is wrong, but rather than assume it never exists, I kept behavior but if Ports exists, which is used in unit tests and what my Docker daemon exposes, then use that instead.

So unit tests look like what I see on my Docker daemon:

        "NetworkSettings": {
            "Bridge": "",
            "SandboxID": "5b3ed04c8e2e65b854bd9a05cf2053e0ae4e932e3e43811197a10255e646ad40",
            "HairpinMode": false,
            "LinkLocalIPv6Address": "",
            "LinkLocalIPv6PrefixLen": 0,
            "Ports": {
                "22/tcp": [
                    {
                        "HostIp": "0.0.0.0",
                        "HostPort": "4584"
                    }
                ]
            },
            "SandboxKey": "/var/run/docker/netns/5b3ed04c8e2e",
            "SecondaryIPAddresses": null,
            "SecondaryIPv6Addresses": null,
            "EndpointID": "ee4961d5a4a1b37548b6c24b3b1be1ee0473a4d9057b0502c6ebe4ebf2129d1c",
            "Gateway": "172.17.0.1",
            "GlobalIPv6Address": "",
            "GlobalIPv6PrefixLen": 0,
            "IPAddress": "172.17.0.6",
            "IPPrefixLen": 16,
            "IPv6Gateway": "",
            "MacAddress": "02:42:ac:11:00:06",
            "Networks": {
                "bridge": {
                    "IPAMConfig": null,
                    "Links": null,
                    "Aliases": null,
                    "NetworkID": "c8a38b79ba988bf1d1301ca810fdceae30636924d57466403047607d14466dce",
                    "EndpointID": "ee4961d5a4a1b37548b6c24b3b1be1ee0473a4d9057b0502c6ebe4ebf2129d1c",
                    "Gateway": "172.17.0.1",
                    "IPAddress": "172.17.0.6",
                    "IPPrefixLen": 16,
                    "IPv6Gateway": "",
                    "GlobalIPv6Address": "",
                    "GlobalIPv6PrefixLen": 0,
                    "MacAddress": "02:42:ac:11:00:06",
                    "DriverOpts": null
                }
            }
        }
    }

I also updated unit tests to test using 0.0.0.0 since that's what the code sets when setting up the SSH port binding.

[codecov]

Codecov Report

Merging #53 (93c3c2f) into master (b47d868) will decrease coverage by 1.26%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #53      +/-   ##
==========================================
- Coverage   84.82%   83.56%   -1.27%     
==========================================
  Files           1        1              
  Lines         290      292       +2     
==========================================
- Hits          246      244       -2     
- Misses         44       48       +4     

Impacted Files	Coverage Δ
lib/beaker/hypervisor/docker.rb	83.56% <100.00%> (-1.27%)	⬇️

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[treydock]

I think the coverage went down because fewer of the conditions got hit since now the first port binding check is getting used. The actual tests all pass though.

[treydock]

@bastelfreak @trevor-vaughan Let me know if this looks good. I've tested this locally on my Mac and it works as expected with Docker.

[russellshackleford]

Adding my 2¢, this also fixed my problem.
Without this change:

Attempting ssh connection to 172.17.0.2, user: root, opts: {:password=>"root", :port=>22, :forward_agent=>false, :auth_methods=>["password", "publickey", "hostbased", "keyboard-interactive"]}
  Warning: Try 1 -- Host 172.17.0.2 unreachable: Errno::ECONNREFUSED - Connection refused - connect(2) for 172.17.0.2:22

With this change:

Attempting ssh connection to 127.0.0.1, user: root, opts: {:password=>"root", :port=>"179", :forward_agent=>false, :auth_methods=>["password", "publickey", "hostbased", "keyboard-interactive"]}

[trevor-vaughan]

Verifying against podman and WSL docker (that should prod any edge cases)