Review community.md for removing utility classes, potentially replacing custom elements/styles

[wise-king-sullyman]

Followup from #4011

Per @mcoker in this comment and this other comment:

I don't know how much it matters, but it's worth noting there are a lot of utility classes used on this page where it looks like we have a stylesheet for other pages? I wonder if we should be more consistent. Also I wonder if we used <Text> headings, if we would need all of these margins and hwhat-not on the headings.

and

I'd expect we have <Grid> props that can replace the use of these .pf-v6-l-grid/.pf-m-* classes?

[nicolethoen]

closed by #4127