adding myself to Contributing.md

[davidmashe]

ghinks recommended I open a PR here, I'd love to help with triage.

[ghinks]

David is another first rate addition from Our organization 😀

[dougwilson]

So @wesleytodd are you still inclined to land and enable these things, or should we document the process and try to expand it out to more folks?

[wesleytodd]

As discussed on the call, I am unable at this time to be the sole person managing this and we want to open it up. I added @davidmashe for now, but we need a better solution. I started the discussion in the triage team board, partly to test out that feature, so when we get a decision we can post it publicly.

[dougwilson]

Closing out PR as I confirmed that @davidmashe is in the group and we are working to pull membership data directly from the GitHub team.