Better enumerate what we mean by "underrepresented groups" in the Values & Principles Committee

In reference to this Twitter thread: https://twitter.com/MarcDrummond/status/1021510982277980168 (there's more there if you click into individual replies; sorry, I can't figure out how to link to the whole thing.)

There's concern being voiced there that the wording of the current Values & Principles Committee Charter is a bit lop-sided in the importance given to various marginalized groups.

Specifically, this section:

Members should collectively be diverse
○ By geography
○ By underrepresented group
○ By job role (coder, business, etc.)

"Geography" is explicitly called out as a place where we need more diversity (which is totally valid, since we tend to heavily skew North American + European-centric); however, the rest of what would be considered "underrepresented groups" is just kinda put there as a collective blob. So if I'm from the Southern Hemisphere, I read this and I feel represented here, but if I'm LGBTQIA2S+ or I'm a person of colour... not so much. It's not clear whether we are explicitly the type of diversity that's sought to be part of the membership of this group, or whether the term "underrepresented groups" is more of a "Cover Your Ass" move. ;)

The suggestion from @MarcDrummond in the thread was to re-use some of the language from the DrupalCon Code Of Conduct, which does explicitly enumerate at least some of these groups.

So in other words, change the second bullet to something like:

○ By underrepresented group (including those marginalized based on gender, gender identity and expression, sexual orientation, disability, physical appearance, body size, race, age, religion and any other protected status)

I would file a patch, but I'm not seeing a copy of this document at https://cgit.drupalcode.org/governance/tree/charters, so I'm not sure how best to do that. So for now, starting here. :)