Use the disc list type instead of circle

[camelid]

Summary

Right now, unordered lists (uls) have the circle list style:

I propose changing this to the disc list style, which is in my experience more common:

Motivation

1. The circle list type looks a bit out-of-place on the Rust website since a lot of the Rust website has a "filled-in" design, e.g., buttons:
   
2. The circles are also so thin that they look pixelated
3. Discs would stand out more on the page so you can clearer see that it's a list
4. Other parts of Rust, e.g. mdBooks, use the disc list type:
   
5. In my experience, the disc list type is more common on websites than the circle list type, so it's a bit jarring for someone used to the other style

Drawbacks

It might be bikeshedding :)

Rationale and alternatives

• Why is this design the best in the space of possible designs?
• What other designs have been considered and what is the rationale for not
  choosing them?
• What is the impact of not doing this?

See the "Motivation" section

Maintenance

N/A

Unresolved Questions

N/A

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@rustbot modify labels: A-design

[XAMPPRocky]

Thank you for your issue! Changing the bullet style makes sense to me.

[camelid]

@rustbot claim