Describe the bug

I hadn't used bashtop in a while and just recently migrated to bpytop. First of all thank you for this amazing piece of software.
Upon trying out the new version, the braille characters are no longer displayed properly in graphs.
This used to work in past bashtop versions, and the issue occurs with the latest bashtop and bpytop. I didn't change fonts in the mean time.

I've tried using a different font, and it seems the graphs only display properly when I select a Bold font style.
So it works with MesloLGS NF Bold, but not with the Regular variant. Same thing for Fira Mono, etc.

Expected behavior

Graphs should display properly regardless of the font style used.

Screenshots

Info (please complete the following information):

• bpytop version: 1.0.21
• psutil version: 5.7.2
• Linux distribution and version: Arch (latest)
• Terminal used: Konsole
• Font used: MesloLGS NF Regular
• Python version: 3.8.5

For reference the font used is the one recommended for powerlevel10k (https://github.com/romkatv/powerlevel10k#meslo-nerd-font-patched-for-powerlevel10k)