Roles re-ordering

[pllim]

This only does the re-ordering. Staffing and descriptions are out of scope.

I took a stab but actual order is open to discussions. We can also add different sub-sections (extra HTML sub-headers) like "governance", "community", etc, but I think that would require splitting out JSON files into many files.

Fix #412

cc Those in the breakout of Astropy Coordination Meeting 2023 @weaverba137 @hamogu @eteq @saimn @aaryapatil