Feat: Support SSH Agent named pipe on Windows runner

[KevinFairise2]

Fixes #746

On Windows, SSH agent use a named pipe, \\.\pipe\openssh-ssh-agent by default.
This PR add some code to try to read that named pipe with winio when running on a Windows runner

[github-actions]

PR is now waiting for a maintainer to run the acceptance tests.
Note for the maintainer: To run the acceptance tests, please comment /run-acceptance-tests on the PR

[blampe]

Thank you for putting this together, @KevinFairise2!

Were you able to test this locally, and did it resolve your issue?

Normally I would ask for a quick test, but in this case that will involve spinning up Windows instances on CI, and I don't think this needs to be held up on that.

[clarkb7]

@blampe I can test it. Can you link some instructions for creating and testing a Windows build? I've only found instructions for macos and Linux/WSL

[clarkb7]

I got help on slack for how to build/test.

screenshot of debugging session showing winio pipe being used

and of 1password ssh-agent recording the activity

summary of build/test
Can cross compile by setting GOOS=windows, and then manually add .exe extension.
or build on Windows via make provider if you have go and mingw.
then put new binary on PATH

$env:PATH="C:\Users\branden.clark\projects\pulumi-command\bin;$env:PATH"

you should see output like

using pulumi-resource-command from $PATH at C:\Users\branden.clark\projects\pulumi-command\bin\pulumi-resource-command.exe

[clarkb7]

@blampe sorry for the @, is there anything else holding up this PR?