Correct the 'cwd' and 'root' columns of processes table on Windows

[mike-myers-tob]

Closes #4384 by pulling the correct Current Working Directory from the process's PEB, which is an approach that —although not a supported API— was already being taken in this table for other fields. Tested on Windows 10 x64.

[theopolis]

Code look good, but I have not tested end-to-end.

[directionless]

@mike-myers-tob I've merged this. I assume you can test master

[mike-myers-tob]

@mike-myers-tob I've merged this. I assume you can test master

https://dev.azure.com/trailofbits/osquery/_build/results?buildId=2898&view=logs&j=a29a2371-0793-5e14-39b9-20eb0beef0db&t=959c2940-2040-5744-cdbd-a6fa34023b5e&l=64

It looks like for Windows Server 2016 (what we use on Azure Pipelines), the code had a soft failure to acquire this information from the PEB. I'll try to reopen the issue, but the merge is fine because at least it works correctly for me on Windows 10 which is an improvement over the prior state of things.

UPDATE: the issue was not with Windows 2016, it's with PEB-less processes, a known issue tracked in #6263 so I will go close #4384 again for good.