fix: do not hardcode Net::SSH auth_methods

[gf3]

Hardcoding the Net::SSH auth_methods option to ["publickey"] prevents alternative authentication methods such as solutions like Tailscale which obviate the need to store and share private keys. The default auth_methods are “publickey”, “hostbased”, “password”, and “keyboard-interactive”—and they are tried in that order. Which means this change will still attempt to use the "publickey" method first and will not break backwards compatibility.

[djmb]

Thanks for this @gf3!

There's a couple of test failures - would you be able to fix those up? 🙏

2023-09-06T07:58:27.0468706Z Failure:
2023-09-06T07:58:27.0469031Z ConfigurationTest#test_to_h [/home/runner/work/kamal/kamal/test/configuration_test.rb:268]:
2023-09-06T07:58:27.0469598Z --- expected
2023-09-06T07:58:27.0469875Z +++ actual
2023-09-06T07:58:27.0470669Z @@ -1 +1 @@
2023-09-06T07:58:27.0472338Z -{:roles=>["web"], :hosts=>["1.1.1.1", "1.1.1.2"], :primary_host=>"1.1.1.1", :version=>"missing", :repository=>"dhh/app", :absolute_image=>"dhh/app:missing", :service_with_version=>"app-missing", :env_args=>["-e", "REDIS_URL=\"redis://x/y\""], :ssh_options=>{:user=>"root", :auth_methods=>["publickey"], :log_level=>:fatal, :keepalive=>true, :keepalive_interval=>30}, :sshkit=>{}, :volume_args=>["--volume", "/local/path:/container/path"], :builder=>{}, :logging=>["--log-opt", "max-size=\"10m\""], :healthcheck=>{"path"=>"/up", "port"=>3000, "max_attempts"=>7}}
2023-09-06T07:58:27.0474431Z +{:roles=>["web"], :hosts=>["1.1.1.1", "1.1.1.2"], :primary_host=>"1.1.1.1", :version=>"missing", :repository=>"dhh/app", :absolute_image=>"dhh/app:missing", :service_with_version=>"app-missing", :env_args=>["-e", "REDIS_URL=\"redis://x/y\""], :volume_args=>["--volume", "/local/path:/container/path"], :ssh_options=>{:user=>"root", :keepalive=>true, :keepalive_interval=>30, :log_level=>:fatal}, :sshkit=>{}, :builder=>{}, :logging=>["--log-opt", "max-size=\"10m\""], :healthcheck=>{"path"=>"/up", "port"=>3000, "max_attempts"=>7}}
2023-09-06T07:58:27.0475165Z 
2023-09-06T07:58:27.0475763Z 
2023-09-06T07:58:27.0476147Z bin/test home/runner/work/kamal/kamal/test/configuration_test.rb:251

2023-09-06T08:00:10.5299217Z Failure:
2023-09-06T08:00:10.5299534Z MainTest#test_config [/home/runner/work/kamal/kamal/test/integration/main_test.rb:54]:
2023-09-06T08:00:10.5299943Z --- expected
2023-09-06T08:00:10.5300308Z +++ actual
2023-09-06T08:00:10.5300523Z @@ -1 +1 @@
2023-09-06T08:00:10.5300966Z -{:user=>"root", :auth_methods=>["publickey"], :keepalive=>true, :keepalive_interval=>30, :log_level=>:fatal}
2023-09-06T08:00:10.5301377Z +{:user=>"root", :keepalive=>true, :keepalive_interval=>30, :log_level=>:fatal}
2023-09-06T08:00:10.5301584Z 
2023-09-06T08:00:10.5301591Z 
2023-09-06T08:00:10.5301758Z bin/test home/runner/work/kamal/kamal/test/integration/main_test.rb:41

[gf3]

@djmb updated!